Brovi E3372-325 LTE-Stick on GL-AR300M

I have a GL-AR300M and try to make it work with the Brovi E3372-325 LTE-Stick. It seems to be a Huawei knock-off.
When logging into the router, i can see with lsusb:
Bus 001 Device 003: ID 3566:2001

I searched the forum and many other places, but I cannot find the neccesary parameters for the /etc/usb-mode.json

It should be something like this:

                "3566:2001": {
                        "*": {
                                "t_class": 224,
                                "mode": "HuaweiNew",
                                "msg": [  ]
                        }
                },

But it isn`t working.
I know that the usb-modswitch under linux is perfoming those steps in order to make it recognizes as a modem:

        /sbin/usb_modeswitch -v 3566 -p 2001 -W -R -w 400
        /sbin/usb_modeswitch -v 3566 -p 2001 -W -R

Is there a setting for usb-mode.json to do the same?

I believe the issue is, that whatever I try, the device is still detected as a mass-storage:

root@GL-AR300M:~# lsusb -t
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-platform/1p, 480M
    |__ Port 1: Dev 3, If 0, Class=Mass Storage, Driver=usb-storage, 480M

Are other models working with this stick?
If yes, maybe someone can provide the usb-mode.json from another model?

Thanks in advance for any helpful tips