I'm not sure this isn't, really, the same question I responded to in another post...this might be a bit clearer, though.
1) If you have 22 sessions, your users get to choose between 22. If they are spread out between locations, with 3 in each location, staff would have to pay attention to the location and chose between them. And, the real question, about excel, NO. I've been told it might be possible to create a csv to upload sessions (not people) but it would take a lot of effort (maybe more than to just build the sessions) and it could break things. Needless to say, I opted to not explore this.
2) If this is a physical activity, I would hope you have proctors or trainers or something. If it is a webinar, there should be some listing of participants that is accessible. If it is an actual on-line simulation...I wouldn't use face2face...unless it is external and you're just giving credit...at which point, I'd get verification from the external provider.
Hope this helps