He is upstairs with Egon investigating a certain type of goo from a class 9 ghost. You are a ghost in this story, you are inside the base while floating around being invisible. You pass by the machine that holds ghosts and you come back to it being interested in it. You try going inside it but fail because it’s ghost proof, you get frustrated and bang on it, causing Ray and Egon to come downstairs and take a look. You go invisible when you see them come downstairs.

Ray: “Egon did you see what banged on it?” he pulls out the ghost detector

Egon: “no I didn’t, did you?” he has his proton pack ready to go