Excel - How to populate calendar on sheet 1, from data on sheet 2

I'm having quite a bit of difficulty building out this calendar to pull data from sheet 2, and populate to the correct cells on sheet 1. To give some clarity into the context of what this is. Sheet 1 is an annual calendar from a template found online. Sheet 2 contains the names and dates of that client's last meeting. This calendar would in effect, go through all the client names and dates, and enter the client names in the corresponding dates on the 1st page. for each "day" on the calendar is comprised of 3 cells, the #, top cell for any holidays if applicable, and the bottom cell for the client names.

I've toyed around with adjusting sheet 1 so that all of the "day" cells actually have the date in it, then using index-match to look up the corresponding clients. The biggest issue I'm running into is that it's possible for multiple clients to occur on the same day. How can I take ALL client name results for a particular day, and then display them all in the same corresponding cell in sheet 1?

So for the novel, just looking to be thorough and not waste anyone's time. Thank you all!

Link to the working version of the file