so last time the Rock-type was tested, the Icy Cave had not been released yet.
Here are the results:
Icy Cave: 33
Spooky Manor: 33
Pleasant Forest: 11
Rugged Mountain: 27
Sparkling Sea: 9
Windswept Sky: 12
I guess Rock also affects the Icy Cave, and not only that but I don't see a major difference between the primary and secondary type :/
also, this is not in the OP, so might as well lol