Nighthawk M6 Pro Mobile Hotspot (AT&T MR6500) & Incoming Connections

Although I couldn't find anything about port forwarding -- a pretty standard feature on most NETGEAR routers -- regarding the Nighthawk M6 Pro 5G hotspot, I did manage to find reference to setting up a DMZ.

So is that potentially my solution for this?  A DMZ infers incoming connections, and I have a spare BR500 router, so potentially could I do something like this (as I may have said previously, I want to use the Ethernet port of the MR6500 and turn off WiFi entirely):

[Public Internet] ==> [MR6500] ==Ethernet==>[BR500]==Ethernet==>[Computer]

I'm not concerned about using the BR500 for my firewall -- I have another one on my network and I am very familiar with that router -- so based on the DMZ feature, it sounds like this should work?  Any problems with this approach?

Since the MR6500 is something like $800, I want to make sure that this works before I make the purchase.

Thanks,

Dave.