Re: If he gets his way...
He might currently have dual nationality, if so, then until we leave the EU, he doesn't need a Visa
As far as I know, he's an Australian/Ecuadorean dual national so he does need a visa to be here as a private citizen. The Ecuadoreans could try issuing him a diplomatic passport over the objections of HMG and force a confrontation over the Vienna Convention, but I'm not sure how much support they'd get for that from other signatories. Shipping him back to Ecuador in a crate under diplomatic seal might be doable though.