The weight and muscle loss are strong indications that he may be misdiagnosed and have type 1 rather than type 2. If that is true, his body is getting little to no insulin which can kill him. Until that happens, his body is literally eating his muscle in an attempt to survive.
The EXACT same thing happened to me last year: I lost 30-40 lbs and the majority of which was muscle. Long story short, I ended up in the emergency room with blood sugar levels above 500.
If he's worried about the money, here's a pretty good way to put it: if he puts this off long enough, the $1000 deductible will be the least of his worries, and he'll need to start thinking about his MAXIMUM out-of-pocket annual deductible which could possibly be more than $10k.
This is NOT something to put off and had I gone long finally decided to go to the doctor to get blood work done, it was serious enough that it could have killed me (and that's not an exaggeration).