So I'm not personally locked into CDMA vs gsm, its just that the carrier appears to be. The exact quote from the device page is
"[US Version] Compatible with GSM Networks including AT&T, T-Mobile and MVNOs (Mobile Virtual Network Operators) who utilize AT&T and T Mobile networks. This device is not compatible with CDMA Networks such as: Verizon, Sprint and US Cellular"
Looking at it more, it sounds like the problem is specifically the 13 band not being supported by the device.
CDMA and GSM are both dead in the US. However MVNOs, who contracturally not allowed to mention the name of the MNO they operate on, have adopted the convetion of using CDMA to refer to Verizon and GSMT or GSMA to refer to T-Mobile or AT&T.
CDMA is a two+ generation old network technology that’s not supported by any major carriers. Curious why you want a device like this? Pretty sure US Cellular is the only carrier of any significant size with an active CDMA network, and even they have been pretty aggressive about moving customers over to GSM devices since 2022.