This looks like a Pro Tools issue rather than a VSL one. I'm also running PT Artist. You say there's no physical iLok dongle on the machine with PT on it, in which case you need to have an iLok Cloud session running. While I've had the odd glitch with this over the couple of years I've had a subscription, most of the time it works OK. You may have done all this but best get the basics out of the way first:
1) In the iLok manager app, first sign in to your account.
2) From the iLok File menu, choose "Open your Cloud session".
3) Then check whether your PT Artist licence is activated. If not activate it by right-clicking and choosing Activate.
4) OK a couple of times.
5) Done.
That's the first thing. Mostly the Cloud session stays open on your computer but occasionally you'll need to log in and open a new session. Happens to me maybe 2-3 times a year.
HTH
Nick
Mac Mini M2 16Gb RAM 500Gb int. SSD 2Tb ext. SSD Pro Tools/Mixbus An awful lot of VI, Synchron-ised and Synchron libraries, amongst others. VSL user since 2003.