My brother is home now. They have determined that he definitely had a stroke but it was a TIA, but it was one of the mildest that a person can have. There is nothing that could have really prevented it. The neurologist said that the numbness and tingling (which he likens to feeling like you arm is asleep) might take up to 24 months to cease and he might never regain the feeling. It's just one of those things.
At any rate, he's on some medications, off work for a bit and should have pretty minimal lasting damage.
Thanks for all your comments and prayers...
And just to clarify, this was David G., NOT David T (who is Steve's brother).