Originally Posted by Belin
I never seen any water when I pressed on it.
That's a good sign!
I see you have an R-Pod 178 so that's in the wet bath then. Only takes a pinhole in the wall covering to let the humidity and moisture from showering cause that, especially where the adhesive wasn't even. Do the blisters appear larger after a shower?
Do note that R-Pods require regular roof inspection and maintenance per every owner we have ever met in our travels. Owners have said sealant around the roof vents cracks pretty easily. That's really true of lap sealants in general. Since you haven't had obvious water, chances are less that you have an actual leak.