Raptor 429 Holding Tank Setup?

[SwooshOG]

I realize rear tank setup may be different, but looking for possibilities of what’s wrong as I’ve not received a response from Keystone on my inquiry.

Here is what I’ve determined with some messy trial and error:
-The coach is labeled with grey tank up front and black tank in the back

-The front tanks contain contents from Kitchen and Full Bath for grey and Full Bath for black

-The back tank (or tanks) contain contents from 1/2 bath

-The front tanks dump and drain as I would expect with the pull of the appropriate valve in the plumbing command center

-The back tank(s) appear to dump directly into exit pipe without any intermiediate valve to control release. In other words, the cap on the exit pipe is the only thing keeping everything contained.

Here is what I’m trying to figure out:
1) Is there an actual grey tank for the 1/ bath or does all content drain to a single tank?

2) Total capacity for grey and black are listed as 82 gallons each, but wondering if they are equal sized at 40ish apiece, or if front is larger than back?

3) Should the release valve that controls the front tanks also control the rear or are these typical configured as separate containment systems. I assume the latter, but understanding how it is supposed to work will help with my discussions with Keystone.

4) if not a central release valve for all tanks, is your 1/2 bath configured with a separate dump valve?

I’ve installed a pipe-end release valve but clearly want something more permanent and for this to function as intended. I know it’s easy to miss things during construction or for failures to happen prior to delivery, so looking for collective wisdom to take this to the right place for resolution.