Your post and the video explain the process much better than I could and was helpful. I did read a not so clear reference to the freshwater tank fill in one of the owners manuals, but completely missed it on my first reading.
Dan and Pam-Natalie-GSD's Sofi & Lindee
2021 Cornerstone 45 B
2018 Cornerstone 45 W (sold)
2020 Chevy Tahoe, etrailer XHD 10500 tow bar, Demco SMI AirForce 1.