Not sure about Queue Manager, but Poser itself could only be put on 3 machines.  Back when Poser was owned by Smith Mirco you had to have the Pro version and the license for that allowed 9999 installs.  Not sure anyone ever had that made machines running on the same network.  One of the Beta testers for 12 had a render farm which had around 16 computers.  I never installed the QM from 12 on other machines since I have one powerful system and a couple of old ones that could not keep up.

Poser 5, 6, 7, 8, Poser Pro 9 (2012), 10 (2014), 11, 12, 13