I've been in the same situation. Showed up to judge, but there were only 24 teams and because I was a previous competitor they knew I could cook. Entry fee was waived and the KCBS reps said as long as I had my own area and wasn't sharing space or equipment they would allow me to cook and make it a qualifier but I had to do all 4 meats.
I was loaned everything. One team basically had a 2nd complete backup setup with canopy, tables, utensils and everything. I was loaned a smoker from another team and other teams donated meat for me to cook. 1 butt, 1 flat, 8 pieces of chicken and 1 rack of ribs. I also borrowed some rub from a fellow cook.
In the end, I actually beat my buddy with his own rub and took 4th overall and also took 1st in pork butt. Needless to say, he has never let me "borrow" anything again. hehehe
I couldn't believe the scores as they came in. I was just as surprised as everyone else, but it just goes to show, that if you have your techniques down, you really can cook on anything at anytime, anywhere. As I didn't have to pay an entry fee it was bonus. At the next competition however, I did give every team that donated items for me to cook with at that contest $100 to say thanks.