I looked at your video. It helped explain the issue. I'd look for better hardware for the bifold door and leave it alone or replace with a regular door. The transition from bifold to regular door sounds like a problem. Unless you put the latch on the outside of the door, I'm not sure how you release it unless you are inside.
If you really want to make the change, I'd try taking the track off the bifold door to see if the hinges still work. I'm not sure they would support the weight.
One other idea is to add a sliding door. I can't say we love ours, but it does work. Look at 2:00 on the video.
https://www.youtube.com/watch?v=ChvVrKIn3KI
