popcornmix, for my edification, is the MVC decoder in your MVC solution ffmpeg and s/w based, and not h/w and Broadcom SoC-based? Asking because w/RPi3, believe it was h/w based.
Also, I personally don't use menus for 99% of my BD/UHD rips. Only have a couple of full ISO's for those that have a lot of playlists and/or separate titles, where having menus do help vs. getting in the way of getting quickly/directly to the main feature.
And this may be an apples vs. oranges comparison, but have been helping test 3D/2D ISO's w/menus with @avdvplus' latest R10 CE test builds, and they're working perfectly. Took him numerous attempts, but he finally did it. If helpful, I can ask him to share any dev insights here that might help w/your LE test builds.
Just tested the same movie (A Turtle's Tale: Sammy's Adventures) in vobs clip above w/Pi5. Played well on my end w/XGIMI Titan Noir Max. Watched about 30 mins.