If you plan to do a qualitative study (and it certainly sounds like it) you may want to dig a bit further in the literature about the nature of qualitative inquiry itself. Terms like Reliability, Validity, and Generalizability are an attempt to mimic positivist approaches and quantitative methods and do not fit well within a qualitative paradigm. Some may give you ‘parallel’ or alternative words to replace these, but (IMHO) this just avoids the problem that a qualitative study is about something else and should not be ‘evaluated’ using quantitative principles.

Your review of the philosophy behind qualitative work should certainly produce a more consistent concept and language for your project.