I was able to get multiple units connected and communicating over gsm by doing a fresh fleet install using the factory image and a basic gsm profile. This allowed the modem profile to configure properly (I guess) because from there I was able to ping via gsm interface. I then moved the device to my application fleet and verified the gsm connection profile. I really can’t say why this worked.
[connection]
id=cellular
type=gsm
autoconnect=true
[gsm]
apn=hologram
number=*99#
[serial]
baud=115200
[ipv4]
method=auto
[ipv6]
addr-gen-mode=stable-privacy
method=auto```