clerk advised to run my card as credit whenever possible over debit.
This is always sound advice. Debit PIN-based transactions are not covered by Visa or Mastercard's zero-fraud liability guarantee. There is the potential for your account to be wiped clean, and you have no recourse for recovery if you choose to purchase goods via debit and PIN.
Suzi, I would also ask around for mortgage broker recommendations. They have access to multiple funding sources, all of which may have different thresholds for co-signers and risk. It doesn't hurt to do the comparison shopping. Keep in mind though, you don't want them pulling your credit willy-nilly, unless you're ready to buy a house. Multiple credit pulls by different banks/lenders over a short period of time are usually treated as one hard pull because the scoring agencies realize you're shopping for a house. Spread out, they will count as multiple, and each one will drop your credit score.
shrift, FWIW, I'd try and spend time with friends. You've been under enough stress, and time with people who are good for you never hurts. Unless the rescheduling causes more stress for you, in which case ignore my advice.
Edit: Glad to hear it, -t! Sounds like a routine process and recovery for him.