Just a try

dist/preview release/loaders/babylonjs.loaders.d.ts

@@ -1081,7 +1081,7 @@ declare module BABYLON.GLTF2 {
                 * Assign an `index` field to each item of the given array.
                 * @param array The array of items
                 */
-            static Assign(array?: IArrayItem[]): void;
+            static Assign(array?: BABYLON.GLTF2.Loader.IArrayItem[]): void;
     }
     /**
         * The glTF 2.0 loader

dist/preview release/loaders/babylonjs.loaders.module.d.ts

@@ -1135,7 +1135,7 @@ declare module 'babylonjs-loaders/src/glTF/1.0/glTFMaterialsCommonExtension' {
 declare module 'babylonjs-loaders/src/glTF/2.0/glTFLoader' {
     import { Scene, Nullable, Mesh, Material, SceneLoaderProgressEvent, AbstractMesh, IParticleSystem, Skeleton, AnimationGroup, Camera, BaseTexture } from "babylonjs";
     import { IProperty } from "babylonjs-gltf2interface";
-    import { IGLTF, INode, IScene, ICamera, IAnimation, IBufferView, IMaterial, ITextureInfo, IImage, IArrayItem } from "babylonjs-loaders/src/glTF/2.0/glTFLoaderInterfaces";
+    import { IGLTF, INode, IScene, ICamera, IAnimation, IBufferView, IMaterial, ITextureInfo, IImage, IArrayItem as ITem } from "babylonjs-loaders/src/glTF/2.0/glTFLoaderInterfaces";
     import { IGLTFLoaderExtension } from "babylonjs-loaders/src/glTF/2.0/glTFLoaderExtension";
     import { IGLTFLoader, GLTFFileLoader, GLTFLoaderState, IGLTFLoaderData } from "babylonjs-loaders/src/glTF/glTFFileLoader";
     /**
@@ -1154,7 +1154,7 @@ declare module 'babylonjs-loaders/src/glTF/2.0/glTFLoader' {
                 * Assign an `index` field to each item of the given array.
                 * @param array The array of items
                 */
-            static Assign(array?: IArrayItem[]): void;
+            static Assign(array?: ITem[]): void;
     }
     /**
         * The glTF 2.0 loader
@@ -2963,7 +2963,7 @@ declare module BABYLON.GLTF2 {
                 * Assign an `index` field to each item of the given array.
                 * @param array The array of items
                 */
-            static Assign(array?: IArrayItem[]): void;
+            static Assign(array?: BABYLON.GLTF2.Loader.IArrayItem[]): void;
     }
     /**
         * The glTF 2.0 loader

loaders/src/glTF/2.0/glTFLoader.ts

@@ -1,6 +1,6 @@
 import { IFileRequest, Buffer, Animation, Scene, Nullable, Mesh, Material, SceneLoaderProgressEvent, Tools, AbstractMesh, IParticleSystem, Skeleton, AnimationGroup, Geometry, VertexBuffer, MorphTargetManager, MorphTarget, TransformNode, Vector3, Quaternion, Matrix, Bone, Camera, FreeCamera, IAnimationKey, AnimationKeyInterpolation, IndicesArray, PBRMaterial, Color3, BaseTexture, Deferred, Texture, LoadFileError } from "babylonjs";
 import { IProperty, AccessorType, CameraType, AnimationChannelTargetPath, AnimationSamplerInterpolation, AccessorComponentType, MaterialAlphaMode, TextureMinFilter, TextureWrapMode, TextureMagFilter, MeshPrimitiveMode } from "babylonjs-gltf2interface";
-import { _IAnimationSamplerData, IGLTF, ISampler, INode, IScene, IMesh,  IAccessor, ISkin, ICamera, IAnimation, IAnimationChannel, IAnimationSampler, IBuffer, IBufferView, IMaterialPbrMetallicRoughness, IMaterial, ITextureInfo, ITexture, IImage, IMeshPrimitive, IArrayItem, _ISamplerData } from "./glTFLoaderInterfaces";
+import { _IAnimationSamplerData, IGLTF, ISampler, INode, IScene, IMesh,  IAccessor, ISkin, ICamera, IAnimation, IAnimationChannel, IAnimationSampler, IBuffer, IBufferView, IMaterialPbrMetallicRoughness, IMaterial, ITextureInfo, ITexture, IImage, IMeshPrimitive, IArrayItem as ITem, _ISamplerData } from "./glTFLoaderInterfaces";
 import { IGLTFLoaderExtension } from "./glTFLoaderExtension";
 import { IGLTFLoader, GLTFFileLoader, GLTFLoaderState, IGLTFLoaderData, GLTFLoaderCoordinateSystemMode, GLTFLoaderAnimationStartMode } from "../glTFFileLoader";
 
@@ -37,7 +37,7 @@ export class ArrayItem {
      * Assign an `index` field to each item of the given array.
      * @param array The array of items
      */
-    public static Assign(array?: IArrayItem[]): void {
+    public static Assign(array?: ITem[]): void {
         if (array) {
             for (let index = 0; index < array.length; index++) {
                 array[index].index = index;