We played in the 14U last year and they did not require us to purchase a bat from them or use a bat they supplied. I did purchase a bat from the M-Power vender while at the tournament but you are not required to use a bat they supply. This was last year and I have not heard of the rule changing.
PG does not supply you bats to hit with, nor require you to purchase bats they specify. They have some sponsors that sell wood bats but PG is not in the bat business. If you are looking to buy a very quality wood bat, I would highly recommend look at Marucci bats.
Save yourself some money, in the long run, and buy a Baum Bat. http://www.baumbat.com/ they are more expensive up front but pay for themselves in no time by NOT breaking.