I'm curious if you ever found a way around this. This happened to me as well and I've been on the phone with TCL and Roku support but I haven't been able to resolve this. I followed all the troubleshooting steps Roku has provided so far, but nothing has worked and they just keep saying it is a networking issue.
My troubleshooting steps so far:
1.Please connect the Tv direct to wall power socket. - Done. Also tried moving it to a different outlet via extension. Neither solution resolved the issue.
2.Connected Mobile hotspot and Ethernet cable. - Done. Still having the same issue. I cannot activate because it errors out when trying to do the software update.
3.Power down the Roku device and restart the Internet Router 3times. - Done. After the third time, I tried to activate again, but it did not resolve the issue.
4. Please make sure the Tv is connected to power , Press and hold for 10 seconds reset button on the device, Please find the reset button which is available on the device or below the device. If not a button you'll find a Reset PIN hole which you can push it with a paper clip or a pen. - Done - this performs a factory reset. I set up the networking afterwards and tried to activate again, but it did not resolve the issue.
5. Repeat the 1st & 2nd options. - Done. I tried again after the factory reset to switch the power outlet and connect the TV to wireless, mobile hotspot, and wired. None of these solutions allow me to activate since it errors out at the software update screen.
6.Please go through the Final software manual update, To set to recent update Version, For that we need 16gb USB, Please go through the below sent Article:-
https://support.roku.com/article/212361468 - Done, but I can't update it since the download image is older than the image on my TV. Download image - 13.0.0.24062. TV image - 13.1.4 build 1510-30
It seems like these are the only troubleshooting steps they know as they keep asking to do the same thing over and over hoping it will resolve the issue.
One thing to mention is that I was also able to reach the secret screen and click on "cycle software update server". Then, clicking on "update software". It would download the same software version and install just fine, but upon restart, I still can't activate it since it errors out at the software update screen.