Using the TMobile ISP Box sim in a Netgear LB1120

I talked to Tech Support last week, asking if the SIM card is locked to the RTL0102, however, they weren't able to answer that and suggested I go ahead and try with a different modem. I'm currently running an OpenWRT platform with a EP06 modem on AT&T. The only T-Mobile band I receive at my location is band 71 (600MHz) when I take the box up on the roof or string it up 40 feet in the air on a tree. So I went ahead and purchased an EC25-AF, which covers Band 71. Long story short, it does not work with the T-Mobile Home Internet SIM. Another call into tech support today confirmed that the SIM only works in the RTL0102 it was shipped with. There are no plans to change that. The new 5G version of the modem-router likely will have no external antenna ports either. So unfortunately, T-Mobile Home Internet is not for people in rural areas, which is ironically who this service was aimed at.