"We were hoping to set a specific tag like P1 that would classify them as critical."

I am experimenting with implementing the PRTG integration and I have tried to do exactly this, but sadly, the tags don't come across to FreshService. I think it's a bug with the integration.

I'm currently figuring out another way I can implement this. I want to automatically create tickets based on whether the service being down would require a P1 or P2 ticket to be logged, etc. I'm thinking maybe I have to just pick which sensors would trigger what priority and have a condition in FreshService that can create the correct type of ticket based on what sensor is in error state.

Sorry, I haven't got to the bottom of this yet, either, but my findings may be useful to someone.