I may not have had the exact issue with running between two machines but I have had the instance where I’ve had to enter in my password to the extent that my verbal language has tainted the air, somewhat.
Here’s my solution that after many clicks of here there and everything seemed to work.
1. trash the contents of the ‘STORAGE” folder in Library>Application support>Apple Qmaster>Storage.
2. Just for the giggles, open System Preferences>Apple Qmaster (32-bit) – make sure you’ve clicked on the RESET SERVICES and stopped the sharing.
3. Click the lock icon.
4. Get out of Qmaster as fast as you can :).
Back to Compressor 4
5. Open it up (probably have to use your password)
6. Click on AppleQmaster pulldown.
7. Open “SHARE THIS COMPUTER”.
8. (In my case) uncheck the “Require these services to only be used in managed clusters” (see attached)

9. Uncheck the “Include unmanaged services from other computers” (This one may be optional in your case, but give it a try – nothing to lose at this point?)
9a. I left the ‘Advanced’ tab alone in this case, IOW all default settings.
10. Restart Compressor and see what happens?
In my case, running a QuickCluster, I was not asked for a password again and now have, thankfully, access to my virtual cluster to crank out work.
I’m hoping that this may either a) provide a solution or b) put you on the path to gain one.
Regards,
Lawrence