The OP said he was disinclined to go into project management. And MBAs now are a dime a dozen. Its certainly not worth spending a crap load of money to get a piece of paper that no one will hire.
As much as I hate to be dogmatically negative, I'd say he's too old to be retrained for coding jobs.
1) Look very carefully at what he said: he specialized in VB.NET. He never bothered to learn C#, which is a centerpiece language for .NET. If he had bothered to learn something outside his vocational concentration, he'd never be posting his question.
2) The only expense to him at this point should be a few books and his time. One shouldn't need to go back to college in to learn how to use C#; particularly if you were adept with computing concepts, algorithms, and development methodologies. If he thinks he needs to obtain paid certification to be "hireable" as a programmer, then he's not really cut out to be a programmer. If he feels the need to ask opinions over whether to make an effort to stay in the industry, then he's as good as done. A professional in his position would be learning C#, latest .NET techniques/additions, and scrounging around for C# contract work to put on his resume. The career life of a 40+ year old coder is not bright at this point, but he shouldn't have a problem finding low paying work, even when competing with 22 year olds and overseas coding shops.
3) Frankly, if he was competent at math, he wouldn't even need to retrain on C#. Retrain on F#, and get a job coding for quants, labs, and large organizations.
4) The only thing I can see him doing that is still computer related, and not programming, would be to recertify as a network administrator. That environment is unlikely to change radically, and there will always be networks needing to upgrade. But you'd have to ask network techs if that is worth bothering at this point.
5) He'd be better off (if living in an non-union state) to retrain as a plumber or electrician. I would imagine after a decade, he'd make more money doing that, than as a programmer.