Hello everyone
Yesterday I was doing Proving Grounds on my healer to gain Silver achievement, and when I was done I left the scenario group and was automatically thrown out of the Proving Grounds scenario. However seeing as Garrisons tend to bug all the time it said 'Transfer aborted: Instance not found' which means I could not get thrown out of my Proving Grounds scenario. This however creates a constant flow, you get in the scenario and it says you'll be ported out to the closest graveyard in 5 seconds and then loading screen to Garrison saying 'Transfer aborted: Instance not found, back in the scenario saying you'll be ported out to closest graveyard, repeat.
Anyway, as I was kicked out of the Proving Grounds I signed up for Gold as healer and was then thrown to loading screen however when I came back in the group you fight with was still there but no mobs appeared, I then did the thrown out and loading screen a few more time and eventually I gave up and signed up for a dungeon!
Now here is the interesting part, right before I was summoned to Skyreach my gold part started and it began on 7/15.
I'm sure you all get my point here, I havn't had a chance to fully test this yet and all that but I do consider it to be very possible to bug Proving Grounds while Garrisons is still bugging.
Cheers!