Got at least one data fetching method working; turns out, we can't use a patched LogicStack to get the data

Vendor/EmbedIO-3.5.2/Utilities/NameValueCollectionExtensions.cs

@@ -0,0 +1,110 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.Specialized;
+using System.Linq;
+
+namespace EmbedIO.Utilities
+{
+    /// <summary>
+    /// Provides extension methods for <see cref="NameValueCollection"/>.
+    /// </summary>
+    public static class NameValueCollectionExtensions
+    {
+        /// <summary>
+        /// <para>Converts a <see cref="NameValueCollection"/> to a dictionary of objects.</para>
+        /// <para>Values in the returned dictionary will wither be strings, or arrays of strings,
+        /// depending on the presence of multiple values for the same key in the collection.</para>
+        /// </summary>
+        /// <param name="this">The <see cref="NameValueCollection"/> on which this method is called.</param>
+        /// <returns>A <see cref="Dictionary{TKey,TValue}"/> associating the collection's keys
+        /// with their values.</returns>
+        /// <exception cref="NullReferenceException"><paramref name="this"/> is <see langword="null"/>.</exception>
+        public static Dictionary<string, object?> ToDictionary(this NameValueCollection @this)
+            => @this.Keys.Cast<string>().ToDictionary(key => key, key => {
+                var values = @this.GetValues(key);
+                if (values == null)
+                    return null;
+
+                return values.Length switch {
+                    0 => null,
+                    1 => (object) values[0],
+                    _ => (object) values
+                };
+            });
+
+        /// <summary>
+        /// Converts a <see cref="NameValueCollection"/> to a dictionary of strings.
+        /// </summary>
+        /// <param name="this">The <see cref="NameValueCollection"/> on which this method is called.</param>
+        /// <returns>A <see cref="Dictionary{TKey,TValue}"/> associating the collection's keys
+        /// with their values (or comma-separated lists in case of multiple values).</returns>
+        /// <exception cref="NullReferenceException"><paramref name="this"/> is <see langword="null"/>.</exception>
+        public static Dictionary<string, string> ToStringDictionary(this NameValueCollection @this)
+            => @this.Keys.Cast<string>().ToDictionary(key => key, @this.Get);
+
+        /// <summary>
+        /// Converts a <see cref="NameValueCollection"/> to a dictionary of arrays of strings.
+        /// </summary>
+        /// <param name="this">The <see cref="NameValueCollection"/> on which this method is called.</param>
+        /// <returns>A <see cref="Dictionary{TKey,TValue}"/> associating the collection's keys
+        /// with arrays of their values.</returns>
+        /// <exception cref="NullReferenceException"><paramref name="this"/> is <see langword="null"/>.</exception>
+        public static Dictionary<string, string[]> ToArrayDictionary(this NameValueCollection @this)
+            => @this.Keys.Cast<string>().ToDictionary(key => key, @this.GetValues);
+
+        /// <summary>
+        /// Determines whether a <see cref="NameValueCollection"/> contains one or more values
+        /// for the specified <paramref name="key"/>.
+        /// </summary>
+        /// <param name="this">The <see cref="NameValueCollection"/> on which this method is called.</param>
+        /// <param name="key">The key to look for.</param>
+        /// <returns><see langword="true"/> if at least one value for <paramref name="key"/>
+        /// is present in the collection; otherwise, <see langword="false"/>.
+        /// </returns>
+        /// <exception cref="NullReferenceException"><paramref name="this"/> is <see langword="null"/>.</exception>
+        public static bool ContainsKey(this NameValueCollection @this, string key)
+            => @this.Keys.Cast<string>().Contains(key);
+
+        /// <summary>
+        /// Determines whether a <see cref="NameValueCollection"/> contains one or more values
+        /// for the specified <paramref name="name"/>, at least one of which is equal to the specified
+        /// <paramref name="value"/>. Value comparisons are carried out using the 
+        /// <see cref="StringComparison.OrdinalIgnoreCase"/> comparison type.
+        /// </summary>
+        /// <param name="this">The <see cref="NameValueCollection"/> on which this method is called.</param>
+        /// <param name="name">The name to look for.</param>
+        /// <param name="value">The value to look for.</param>
+        /// <returns><see langword="true"/> if at least one of the values for <paramref name="name"/>
+        /// in the collection is equal to <paramref name="value"/>; otherwise, <see langword="false"/>.
+        /// </returns>
+        /// <exception cref="NullReferenceException"><paramref name="this"/> is <see langword="null"/>.</exception>
+        /// <remarks>White space is trimmed from the start and end of each value before comparison.</remarks>
+        /// <seealso cref="Contains(NameValueCollection,string,string,StringComparison)"/>
+        public static bool Contains(this NameValueCollection @this, string name, string value)
+            => Contains(@this, name, value, StringComparison.OrdinalIgnoreCase);
+
+        /// <summary>
+        /// Determines whether a <see cref="NameValueCollection"/> contains one or more values
+        /// for the specified <paramref name="name"/>, at least one of which is equal to the specified
+        /// <paramref name="value"/>. Value comparisons are carried out using the specified
+        /// <paramref name="comparisonType"/>.
+        /// </summary>
+        /// <param name="this">The <see cref="NameValueCollection"/> on which this method is called.</param>
+        /// <param name="name">The name to look for.</param>
+        /// <param name="value">The value to look for.</param>
+        /// <param name="comparisonType">One of the <see cref="StringComparison"/> enumeration values
+        /// that specifies how the strings will be compared.</param>
+        /// <returns><see langword="true"/> if at least one of the values for <paramref name="name"/>
+        /// in the collection is equal to <paramref name="value"/>; otherwise, <see langword="false"/>.
+        /// </returns>
+        /// <exception cref="NullReferenceException"><paramref name="this"/> is <see langword="null"/>.</exception>
+        /// <remarks>White space is trimmed from the start and end of each value before comparison.</remarks>
+        /// <seealso cref="Contains(NameValueCollection,string,string)"/>
+        public static bool Contains(this NameValueCollection @this, string name, string? value, StringComparison comparisonType)
+        {
+            value = value?.Trim();
+            return @this[name]?.SplitByComma()
+               .Any(val => string.Equals(val?.Trim(), value, comparisonType)) ?? false;
+        }
+    }
+}