Check is Online

Since Server 2016 it's difficult to see, if a server has been rebooted with the "Check is online" function.

That's not a bug of RDM, it's more an "issue" of newer Windows versions, where RDP is still available, while starting the reboot of a server.
Maybe you'll be able to find a way to improve the "Check is online" function within RDM, to "really" check if the server is back online after a Windows Update has been installed.

Maybe some kind of function, that check is online will only reconnect to the server, if at least one or two pings have been missed, since starting "Check is online".
I often use this function to reconnect to a server after doing Windows Updates.