Thanks for the responses guys. I think we have a lid on the situation. I had a serious chat with him and laid down what can go wrong with our old approach and if we don't think about these things up front, without making it seem like I was angry or lecturing him.

I tend to be a better strategic thinker, i.e. picking venues, types of groups to go for, who's on the team for that night, etc. Luckily one of the guys is pretty much a tactical genius with really solid core skills. He came up with following plan to deal with the bad wingman:

Plan A (just you and him):
1. Get him wasted.
2. Find target
3. Send him in
4. Chill and wait a few minutes
5. Go up to girl and rescue her
6. You’re her hero and get some!

Plan B (with 3+ of you)
1. Wing him hard and get him sorted ASAP
2. The rest of the field is yours!
3. We later get him to get his girl to buy us rounds!