Once the default HTTP(S) ports are changed, they do have to be referenced in the URL address.
What I have noticed from the logs is that the router looses mobile data connection multiple times, almost immediately after it is established. This might be the reason, why the device is unreachable remotely. Have you tried pinging the public IP address, the router is assigned with, as the device should reply to ping requests by default. Failure to receive replies indicates connection issues.
The reasons for disconnects can be various. The current suspect is the signal quality, as the LTE band 8, the router was connected to during the file generation, had poor RSRP and SINR values:
I would suggest to try manually setting different LTE bands, as instructed in this video. Alternatively, a different device placement of a directional antenna can be tried as well.
Also, for comparison, could you check Status -> System page Internal modem section of each router to see, if the devices have the same modem modules with the same firmware versions?