The lesson you highlight is extremely valuable. But don't underestimate your instinct for a good idea. The flaw here was not your talking to a mid-level manager and being excited. The flaw as you point out was not listening to your team and waiting to pursue the other opportunity. Gather momentum, and once that snowball is rolling downhill without you pushing it, then it might have been wise to POC what a franchise solution might look like.

One other question I have is such. With the franchise-onboarding idea, who is the customer? Is the customer the franchisee or the franchisor?