Item rendering on model hand bones in Geckolib 3.0.java

private static final ItemStack chaingun = new ItemStack(DoomItems.CHAINGUN.get());
private IRenderTypeBuffer rtb;
private ResourceLocation whTexture;

@Override
public void renderEarly(ChaingunnerEntity animatable, MatrixStack stackIn, float ticks,
        IRenderTypeBuffer renderTypeBuffer, IVertexBuilder vertexBuilder, int packedLightIn, int packedOverlayIn,
        float red, float green, float blue, float partialTicks) {
        this.rtb = renderTypeBuffer;
        this.whTexture = this.getTextureLocation(animatable);  
    super.renderEarly(animatable, stackIn, ticks, renderTypeBuffer, vertexBuilder, packedLightIn, packedOverlayIn, red,
                green, blue, partialTicks);
}

@Override
public void renderRecursively(GeoBone arg0, MatrixStack arg1, IVertexBuilder arg2, int arg3, int arg4, float arg5,
            float arg6, float arg7, float arg8) {
    if (arg0.getName().equals("right_hand")) {
        arg1.push();
        arg1.rotate(Vector3f.XP.rotationDegrees(-140));
        arg1.rotate(Vector3f.YP.rotationDegrees(5));
        arg1.rotate(Vector3f.ZP.rotationDegrees(15));
        arg1.translate(0.05D, -0.8D, 0.5D);
        arg1.scale(1.0f, 1.0f, 1.0f);
        Minecraft.getInstance().getItemRenderer().renderItem(chaingun, TransformType.THIRD_PERSON_RIGHT_HAND, arg3,
                arg4, arg1, this.rtb);
        arg1.pop();
        arg2 = rtb.getBuffer(RenderType.getEntitySmoothCutout(whTexture));
    }
    super.renderRecursively(arg0, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8);
}