Hmm,
Our policy as prescribed by our naturopath is that anything that seems to cause a flare is discontinued, with symptoms noted. If this is a supplement you feel is necessary it can be reintroduced later using the start low and slow method.
Can you get probiotics another way? Fermented foods, miso, kombucha, etc?
Sometimes it's better to get it in a food as that particular supplement may be tolerated better as the food contains other nutrients that work in an entourage effect.
Good luck, we've had horrible OCD flares here too and it's no fun.
You sound like a strong, intelligent, proactive person!