Nothing to see here

No, as long as the total stays under 20k.

Try to work out what the balance figure will be two days after the intermediary presses the submit button - assuming they talk to you on the day they do it.

A difference of £20-30 should not cause any issues anyway but it's good to be accurate

You're fine on both counts. The DRO Team (I believe) get a simplified report from Experian just showing debts and balances. They do not dig into everything in fine detail - they assume that the intermediary has done that.

Secondly, a third party can do what it wants with its money.

The joint bank account does mean that your wife's credit history will be linked to yours. I hope she realises that. It may be worth her getting a new account now in her own name, before the DRO hits. It's unlikely that the existing account will be closed just because your name is on it but (Nat west are known for this) it may be downgraded to a basic account.

Your credit file is stuffed for 6 years whatever happens.

Why not do a DRO now, get it finished by June 2020?

They seem very vague about when they can give you the money (12-18 months) but, when they do, you can do something more useful with it, provided they don't just dump it in your account during the moratorium.