A game where you bet on outcomes? That is absolutely my jam.
As a kid I played Hot Dog Vendor, a text based game on early PCs where you buy supplies for your stadium hot dog cart guessing based on weather and if it's a big game day or not and stuff like that, and you make or lose money each guess. No fancy UI, mostly just luck, and I loved it. I remember if decades later.
I also think your game suggests something else going for it: plot. The woman who gives you the money initially suggests a wider story and something more than just betting. I wouldn't drop that even if it's not part of the core mechanic you're exploring first. It is some of what initially pulls me in.