Just go balls out and get a Star-batt Mini case...they make mounting solutions as well. Not cheap, but balls out!
https://star-batt.com/?v=0b3b97fa6688
So where are you connecting the + lead from AGM battery to the DC-DC charger? I can't seem to find it in the pictures. I assume it is just wired in to one of the available bus points on the AGM + factory connector?
Go to this thread. There is lots of forscan discussion. The spreadsheet in the attachments tells you what to change and what module it is located in.
https://www.bronco6g.com/forum/threads/forscan-bronco-working-spreadsheet-double-honk-sport-mode-chimes-seatbelts-and-more.28489/
I think the pandemic did create a pop in this space. And I also believe some of that pop is "dying". I have always been a watcher and I am just now working myself into putting something of a "rig" together. I liked the video...just another opinion...not really in any position to criticize...