You will get a 3-star wanted level (that will shortly change to 69 stars) if you enter PMLand's grounds and are not Soapy or Keykey. Malicious bodyguards, tanks, and 420 helicopters will be sent to your last known location. It's impossible to outrun them without paying a fine of $2012,1337,690,420.
In 2018, Pinky dies in this place due to him being left out by Iogr, Soapy, Jomz, and KewlGemur during the Iogrbomb attack.
What happens if you trespass
In other words, stay out.