Sorry about your seedlings.
Damp-off stinks...
I remember years ago reading that someone saved some of their damp-off affected Brug seedlings by treating them like cuttings. As I remember, somewhat fuzzily, they used clean nail scissors to cut about 1/2" inch of the infected hypocotyledonous stem off. Then they dipped it in rooting hormone (maybe with fungicide added?) and treated it just like a cutting (with a humidity dome, etc.) The seedlings produced new roots from the hypocotyl. I don't think all of them made it but some did so it might be worth a try if it happens again.
