ConnectCore 6UL Eth0 NetworkManager Problem

I am having trouble using the ETH2 port on the ConnectCore 6UL Pro.

From what I read, the Ethernet hardware is mapped to Linux like this:

PHY | LINUX

ETH2 | eth0
ETH1 | eth1

So, in Linux, I tried to connect to eth0 (which uses the physical ETH2) using networkManager (nmcli). I set a static IP, manual ipv4 method and connect. With eth1, this works 100% of the time.

With eth0, I can see the connection using nmcli con show but in ifconfig eth0 I see no ipv4 address assigned, and the connection does not work. I can then assign an IP to eth0 with ifconfig eth0 ###.###.###.### and the connection will work for a few seconds. After those few seconds, the connection disappears from nmcli con show and the IP disappears from ifconfig eth0.

What Is up with ETH2 (Linux eth0)? Is there something I am missing when setting this up in Linux? Is there something I should be doing in the device tree when compiling the OS?

Are you using stock DEY-2.6 images?
https://www.digi.com/resources/documentation/digidocs/embedded/dey/2.6/cc6ul/yocto-gs_t_program-fw_6ul