Very awesome of you sir.
It seems that a lot of the charity events I play in, the fund raising revolves around raffles and door prizes. A lot of them sell mulligans which don't cost you anything, but... I played in one where you could buy 3' sections of string which could be used to pull the into the hole and not count a putt. It was a nice alternative to a mulligan because you still had to get the ball to within 3' before you could use it. Back to the door prize tickets, if you can get sponsors or donors to give you lots of goodies to give away, you can create opportunities to win tickets. One scramble I play has a par 3 challenge where each player can pay $5 to participate on each par 3. If they miss the green, they get 1 ticket for trying, but if they hit the green, they get 5 tickets. You can also bet on other players to hit the green. I've seen this done where players bet on whether they hit the fairway on a tight par 4. I even played in an outing where you could pay a long drive competitor to hit a drive for your group.
I know there are mixed feelings about outings on here. I am just giving you some fundraising ideas.
Best of luck to you!