We aren't looking for a forward facing seat - as the post said, we are looking for rear facing only, and looking for specific seat recommendations. I did see your video and the rear facing seat you've used does not appear to be a good model for newborns which needs lots of recline so their head does not drop forward. If you have any specific recommendations that fit the OP criteria, I'd love to know, thanks.Front facing seats for newborns is extremely dangerous.
Look into putting a more narrow seat into the middle position. All child seats work well with a seatbelt.
At about 3 minutes in you'll see what I'm taking about.