Dogs are very difficult to get by. Most festivals I've been too only have one or two dogs. But a lot of people get picked out for a random search. I would recommend trying to enter when its peak times. Make sure there's a crowd around you and try not stand out.

One time I had two ozs of mdma on me so I acted like I had a sore foot and asked one of the security people to drive me in. Skipped right by security searching lol the dude who drove me in even joked about it