Hello there, Lori. Yes, the toner appears to exhaust quickly and heating the toner will speed things up. Best to have a print in the toner while increasing temp, in order to see how much effect.
Additionally, different warm toned papers will gobble toner (selenium and gold) at wildly different rates. I would consider Ilford MGWT to be on the slow (and less dramatic) side of the spectrum.
In any event, the natural urge is to add more AuCl, or heat the tray. Heat the tray first. And don't tag your toner as DOA and pitch it. More responsive papers may come into your possession in the future.