If you switch session, not only you won't solve your own problem but you will bring this problem to other players as well - basically, you will "infect" this session. If any other player will try to switch session after that - he will bring this prop (infect) to other lobbies too. And so the "infection" will spread further.
You need to completely shut down the game in order to get rid of this.
Doesn't quitting back to single player get rid of them?
We were doing Criminal Mastermind and some hacker placed a rotating Wind Turbine right next our heist appartment in a freeroam. It was transferred to a setup mission - we were extremely lucky, rotating blades didn't kill any of us (I believe, it could). We all tried to go to single player and back - but it didn't remove this ****. Restarting the game was the only thing that solved the problem.