I am collecting data that includes the customer's desired dates. I would like for them to be able to see what is already on the calendar before submitting their form, have their entries auto populate on the calendar AND if an entry is changed, have the calendar updated. This is somewhat complicated by the fact that I do not have FTP access or a sandbox. I am working on that with our host, but in the meantime I am rather hamstrung in that area. I am using FF Elite.
When filling out their form, the event may have 1, 2, 3, 4, 5, or 6 sessions. Currently I have a dropdown asking how many sessions, then it shows the appropriate number of Date, Start Time and End Time fields.
Things I have tried:

• Making a calendar view based on the form they are filling out - this works great for 1 session, but I am struggling to capture sessions 2-6 because in the calendar view, each event must be a separate entry
• Making a second form "CalendarBuilder" and using the API to pass the relevant information for each date as a separate entry, using conditional logic based on the question in the main form about how many sessions. It works beautifully for populating the view, which is embedded in an HTML field in the main form. 
  • I included a field for the main form entry ID and for session 2 labeled it [id]-2, etc, so each session has a unique identifier. 
  • I can send a new entry to CalendarBuilder when they edit the main form, but that just adds another event and does not remove the original one, which will get confusing quickly
  • I thought maybe I could give them access to only edit their own events and allow them to remove it themselves, but because the API created the event, that does not seem to work. (And I also think many of them would get confused by this step).
• Sending each date to a Google Sheet and having Zapier create a Calendar event. The Google calendar is embedded in an HTML field in the original form. Works great, but again, edits just add to it, don't remove the old. Giving users permission to edit the Google calendar is beyond many of them (they try to access it from their spouse's account, the account they created 10 years ago and forgot about, etc.) 

I am working with very low tech folks who will get frustrated and overwhelmed at multi-step (much less multi platform) tasks, so I am trying to keep it as simple as humanly possible on the frontend.
Any suggestions that I may not have thought of? I can see the great potential here, but without access to hooks, it complicates things. A local company built our website and is hosting it. We have full access to the Wordpress backend, but no cPanel, FTP, etc. and they are being slow in responding to my request for access, so I need to move forward without it for now.