I've always assumed the unreleased songs mentioned in the 1993 Mexico deposition are recorded to different degrees of completion.
This is a hunch on my part though
Given the amount of songs, noted in the deposition, we've now heard since it was recorded for one. Although for me the biggest indication is the recognition in Mike's eyes when certain songs are mentioned. It's as if them being mentioned struck a chord with him, I doubt you'd have that with just lyrics on a sheet of paper or even just instrumental grooves.
Also pre 1993, Mike worked hard and did have a scattergun approach were he was constantly working on something, which unfortunately does mean a lot is incomplete.