Hello
So typically it's pretty difficult to get a calcium toxicity....but i too did the same thing a few summers ago with my outdoor and gave like a quadruple dosage. The plants got spotty curly and discolored edges.
If you're unwilling to flush the plant, then I think you should at least do a heavy properly ph'd watering to attempt to wash some lingering amounts out. Unfortunately the damage done to the leaves will not repair, but if it can not spread further then that would be good enough. The bad thing is calcium has a tendency to get stuck once it's there...so more damage may follow for a little longer.
You could try dropping the ph low below 6 in the hopes it will lockout the calcium, but that could cause other deficiencies. Calcium is also less available in the cold so possibly watering with cold water and keeping roots cold could also help lockout the Ca. If you choose to lower the ph into a more acidic range that could help, but try feeding with nutrients with little to no calcium and see if it helps. Watch for other deficiencies though because the calcium problem could end up locking out some other crucial elements.
*there are some bottled products that you can water with to blast out any excess nutrients like foxfarms sledgehammer, or clean fruits by greenbuzz.
Good luck with the grow, i hope you can get her fixed up nice and quick. ✌️