While we were staying at WL in March it was my wedding and also my birthday.. We called the front desk and asked about having a birthday cake.. I can't remember if she took care of the request or if she transferred the call, but room service brought up two small (but very rich) cakes with candles, plates, forks, napkins etc... While not beautiful birthday cakes, as they were chocolate cakes with "Happy Birthday Jon" wriiten on them with frosting, they were very good.. I can't remember the cost, but I do remember thinking that the cost wasn't as much as I thought it would be..
If anyone is staying at the Wilderness Lodge, I would suggest having the birthday party on the fourth floor terrace overlooking the pool..