What's the difference between 29.97p and 29.97fps?
A 29.97p (p = progressive) video is 29.97fps (fps = frames per second) but not all 29.97 fps video will be progressive. Some will be interlaced, (29.97i) having 59.94 "fields" per frame.

So there may be no difference at all. If Premiere doesn't indicate whether the files are interlaced or progressive, use a tool like MediaInfo.