Dice game- looking for help

Hello all! I am running a game online on roll 20 and the PCs are about to arrive in a gritty pirate town. I would love to include a rigged dice game where the pirates are trying to cheat them. But because we are playing online I can’t think of a way to run it (I don’t think roll 20 allows fake dice rolls)

any suggestions would be appreciated! 

I want to game to be simple and most of the fun come from the players using skills to discover they are being cheated, or cheat the pirates in return.

thanks in advance! 

Liars Dice is a great option - https://youtu.be/fF4aYyP_ahs?si=BMsHXa2rLONmM9Yi

I turned Liar's Dice into a free app with an option to give your players (and npc's) access to cheats so you can play a properly crooked game of Liar's Dice!
https://haa-gg.github.io/Liars-Dice/

It's a work in progress so let me know if you think of improvements

Note: to turn on the cheats, start a new table, go to settings and turn on "Honor System Cheats"