Hi,
1.Are there any other methods that worthy to troubleshoot the disconnection problem?
2.To rebuild or reconfigure any roles of server, you have to back up some data and reconfigure the settings as before. You should also consider the settings of RD Collection if it is used to belong to as well as the UPD path if was correct or not. Otherwise, it is same like go from the scratch to add a new RDSH server.
Migrate virtual desktop collections
Hope this helps and please help to accept as Answer if the response is useful.
Thanks,
Jenny