Version QSC versus QS

We deploy the same TeamViewer exe to all our clients. One client launches QuickSupport and we get notified in the Management Consult of an incoming request. Their TeamViewer version # ends in "x.xxx.QSC".

Another client launches QuickSupport the same way, but they get a different console where they have to give us their meeting Id and password. Their TeamViewer version ends in "x.xxx.QS".

I looked at the logfile and the "QSC" version looks for a finds a Certificate while the "QS" version doesn't even seem to look for a Certificate.

We cannot figure out why the "QS" customer is launching now with a meeting Id and Password, whereas before it would automatically appear in our TeamViewer Management console like all our other clients. Something has changed and we don't know what.
See Screenshot.