Even though Rudy had scared Scott away and warned him not to get involved with him or Reina anymore, he didn't learn his lesson.
Rudy had used his powers in front of Scott, and as expected for his personality, Scott wanted to catch Rudy using his powers red-handedly, record footage and spread them everywhere.
Scott knew he would never be able to win against Rudy in any way possible, so the only thing he could do was to destroy him socially.
In truth, Mark had also tried to break in last night when Rudy and Reina were having fun, but Reina's moan drew Mark away.
He thought there was a howling dog in the waterpark. The next day— today— he came again in disguise and entered the waterpark for the first time. He searched through the waterpark to see if there was any guard dog, but after inspecting for 10 minutes, he didn't find anything and left.
Soon after, Rudy and Alice had arrived.
After confirming that there was no dog in the waterpark, Mark broke in at night.
