#1 - There are some known issues around the Remote Control Service Crashing......Support can likely get you some updated test modules to see if that helps.

#2 - Test doing the Remote Control with a "Super Administrator".  Remote Control requires the person doing the operation to have Permission to Both the Device Object and the Logged in User.  Missing rights to the Logged on User can result in the Remote Control Session working at the Logon screen but being terminated shortly after user logon.  It's possible the termination is leaving RC in a bad state.....or course it may just be terminating due to a crash.....where #1 may help.

Like I said, there is no logged in user in a Zenworks sense, as Zenworks isn't even configured for users at all, it's working strictly with devices only in this setup (don't ask, not my idea). I'll check if the service crashes, that's a good hint.

I don't think it will help, but on the RC service in the Services Control Panel, there is an option to "Enable Actions for Stops with Errors" that Might help the service to recover.  It has other settings so it will recover from a crash, but it seems it does not in all cases and this may help cover some of those cases.  Indirect Feedback from another customer indicates it may not help, but its the only suggestion I would have.  Other than that, there is some updated test code that fixes some crash exceptions.....