I don't know if that will work or not. I don't believe it will. Explained below.
I wired this back in 2014, so finding some details is harder than it should be. However, this is the relay I bought:
This takes the 120 volt output from the iVac Pro Switch and provides the contact closure to the RL160. The switch you show is 12V, so the iVac Pro Switch would blow it out.
I'm looking for pictures of how the wiring was done inside the RL160. If I still have the photos, they are on a Mac that hasn't been used in five years. I'll let you know what I come up with.
