3124 can be had with two fridges if you order that option specific from the factory. Someone on the TM Fans Facebook page has one like that. They love it. If I ever figure out how to transform my 3326 from KS to KB, it will have two fridges.
Also note, I think the floor plan is incorrect on the TM website for the 3124KB. I believe it now has the same dinette/bed configuration as the other models, no longer has the one longer couch.
As for the weight distribution hitch, I tow a 3326 with a Ram 1500 EcoDiesel. Does it NEED a WDH? No not really. But it goes oh so much nicer with the Andersen No-Sway WDH. I highly recommend that one. Again, a bunch of us have that WDH on the Fans page and we all love it. I’m not familiar with the Tundra’s towing numbers but you may be pushing the tongue weight limits of the hitch without a WDH.
https://youtu.be/HRoQ_yQZQwQ