Where generally are you located? I would be happy to share live rock, sand and filter media with you to get your tank started again. I've also read that cycling with livestock isn't the abomination it has been made out to be and not interested in arguing the point in this case. I also have a Chromis and a cardinal you could have. Chances are you aren't close to me, but the offer stands if you are, and I'm sure there are others from this forum who would be willing to do the same if they are close enough. I trust Divers Den from Live Aquaria to ship healthy fish once the tank is cycled if you don't have anyone close you can trust.
Please feel free to PM me. Best wishes and give your son an extra hug for us. We'll be routing for him and your whole family. Take care