Bathroom Discoloration

[es-kah-pay]

Hello friends, I'm new to posting here but have found so much useful info on this site already so let me start with a "thank you" and a "happy to be here". Now on to my situation...

I recieved my trailer about 2 months ago and am living in it ever since. One thing I haven't done is used the bathroom to any extent whatsoever as I am able to use a shared bathroom space at the property where the trailer is parked.

Very shortly after being in the trailer, maybe 3or4 weeks, I noticed yellowing of the bathroom. Strange but it seemed to be localized to where the shower curtain was touching the fiberglass bath insert, so I chalked it up to a weird reaction with the plastic and the fiberglass, and removed the shower curtain. Then I check again a few days ago (about another month gone by) and the yellowing is vastly worse and spread to several areas in the bathroom.

I reached out to ETI and recieved exactly this response back, "I had a chat with our fiberglass team, and he suggested that the bathroom vent could be leaking causing the discoloration in the attached photos. I have attached a video on how to remedy the leak, do you have silicone? I can have some sent to you under warranty. When it comes to removing the discoloration, he recommended to start with Vim kitchen cleaner, it works well and is less susceptible to creating scratches! Do you have any on hand?"

Regarding that response from ETI first let me say that I indeed have seen evidence that the vent was leaking, and it's been on/off rain/snow here in the PNW where I'm parked, but I could never find visible drips coming into the bathroom from the vent. At the time I concluded it must be condensing through the vent or leaking from an area of the vent that I was never finding when I was checking. Yes, there is water in the bathroom that could have only gotten there from some sort of leak. No, I don't know exactly where it's coming from. The video that the gentleman sent was less than helpful to be fair, especially when the silicone applied to my vent looks perfectly how he explains it should be. I have a few questions for the forum goers...

Anyone experienced this same thing? (keep in mind this is after 2 months and no use)
Does the leak that the ETI rep described mean that there is now water between the exterior of the trailer and the lining of the bathroom insert ie the interior of the trailer?
Am I just supposed to remedy this situation on my own and not raise any sort of hell with ETI about it? (this is my first big purchase in life and my house on wheels)