Yeah, i feel your pain 
I damped off a few seeds not too long ago, and I’ve had great seed-popping game up until that
My typical method is each seed in a solo cup half full of coco, that coco flooded with cal mag-rich water pH to 6.2ish. Baggie for a dome until they pop, almost always 2-3 days upwards of 4 days, never taken more than 5 days.