But could the hundreds of employees continue to make changes to the DB if it was moved out of sheets?
I lasted 3 months only, got tired of the sudden meetings discussing why can't we give fast and accurate results.
Also, the fact that you offered to do it for free makes me question your motivation. I think you were trying to make your own job easier at the cost of the users no longer having the thing that worked for them.
It can be very difficult to replace spreadsheets because the UI has had 30+ years of iteration.