This was not the issue

Took 4 minutes

engine/engine-paper/src/main/kotlin/com/typewritermc/engine/paper/GlobalClassloader.kt

@@ -16,23 +16,19 @@ import io.papermc.paper.plugin.provider.classloader.PluginClassLoaderGroup
  * To solve this, we hack around the Paper classloader system to get a classloader that has access to all classes.
  */
 class GlobalClassloader(
-    private val groups: List<PluginClassLoaderGroup>,
+    private val group: PluginClassLoaderGroup,
     private val requester: ConfiguredPluginClassLoader,
 ) : ClassLoader() {
     override fun loadClass(name: String, resolve: Boolean): Class<*> {
-        for (group in groups) {
-            return group.getClassByName(name, resolve, requester) ?: continue
-        }
-        return super.loadClass(name, resolve)
+        return group.getClassByName(name, resolve, requester) ?: super.loadClass(name, resolve)
     }
 }
 
-@Suppress("UNCHECKED_CAST")
 internal fun globalClassloader(): GlobalClassloader {
     val storage = PaperClassLoaderStorage.instance()
 
-    val groups = storage.javaClass.getDeclaredMethod("getGroups").invoke(storage) as List<PluginClassLoaderGroup>
+    val group = storage.javaClass.getDeclaredMethod("getGlobalGroup").invoke(storage) as PluginClassLoaderGroup
     val requester = plugin.javaClass.classLoader as ConfiguredPluginClassLoader
 
-    return GlobalClassloader(groups, requester)
+    return GlobalClassloader(group, requester)
 }