If you're not taking chests from anyone, having someone that cleared in the party is a positive for the rest of the group. Tell the OT to bite you.

Four weeks of virus prog also points to a problem within the group. Either there is too much time being wasted between pulls resulting in not enough actual practice time, the raid's strategy is flawed, or a member needs a helping hand. I would make a mental note of the repeat offender(s) and reach out to them privately after the raid. It's possible they've misunderstood the mechanics.