A corporation will only stop doing business with whoever if it becomes unprofitable.
I could sell guns to the IRA and very publicly, except quite a lot of people wouldn't like it and I'd be thrown into jail, which would mean I would have to stop selling guns, which isn't profitable.
If I had a scapegoat who could take the fall for me while I continue selling guns, as long as that scapegoat isn't integral to my profits, I'll gladly let them take the fall and continue selling guns, profitable.
If all my transports full of guns keep getting blasted to bits in a certain area, then I may stop doing business there as it isn't profitable anymore.
IC can pull out of Rheinland if they want.
Why would they want to though?