Yeah... I'm an idiot... but, in my defense, I've been doing mostly Python programming lately!!

The
correct the syntax for "combining" multiple outputs for a print() statement in LUA is ".." not ","

Try:
function dobet()
print("Roll: " .. lastBet.Roll)
if (lastBet.Roll < 3.3 or lastBet.Roll > 96.7) then
chance = 49.1089
end
...
Lol, i probably could have just looked up how to do a print function, but it all looked good to me so I didn't. Lemme try that one.
So I was fortunate to hit both sides withing a few bets of each other and all within a couple bets of starting. Here's what I got:
Betting 0.00046871885 at 97.2549% chance to win, high
Roll: 0.775
Betting 0.0009374377 at 49.1089% chance to win, high
Roll: 91.807
Betting 0.000469670937109375 at 97.2549% chance to win, high
Betting Stopped!
Roll: 96.689
Betting 0.00046970763046875 at 97.2549% chance to win, high
You can see that on the low end (first roll there), it works fine and the payout changes. But the last shown roll is 96.689 and should have made the next bet go to the 49%, but it didn't