[henryl]

We had an old demo but we have since revamped the entire architecture. Would a video suffice?

[JabavuAdams]

"Required", "suffice". It seems you're looking for guarantees where none are possible. Think in terms of increasing your odds.

IMHO, a good demo can help you sell. You're selling your team. What can you do to help yourself convince investors that you are smart and can execute?