How to check Verizon U620L modem mode

I was trying to check the mode status of a UCB U620L modem on my GL-MT1300 router, but when I try to run lssub, it says it is not found.

Is there an alternative command that can/should be used?

You can get USB device info here:

cat /sys/kernel/debug/usb/devices

Thanks for that additional guidance. This allowed me to verify what I was needing.