As of a couple of years ago RVC classified the vet program (4 or 5 year entry) as tier 4 undergraduate. Thus, spouses cannot get visas through a student in the vet program anymore. (Not exactly sure I remember the classification correctly, but I'm sure spouses can't get visas anymore)
From what I know it can be quite difficult to find a job in the London area without a visa. That being said, it also really depends what field he works in. He'll have to apply for his own visa by being sponsored by an employer here, completely separate from your student visa.