Learn markdown, please. The format of plan.md should properly render lists, headings, etc...
A few comments:
I'd look for a library that does the odds calculation for you. This is a pretty deep rabbit hole. You all can do it, but it will be a little time-consuming.
The language for the odds calculation is not very relevant. Anything will work. What matters more is the library you're going to use for QR code reading.
Since people aren't going to want to play this along side their computer, you might consider making the web-interface be mobile accessible. This is not necessary, but would really make this actually useful.
You seem to think that QR reader will be an external device from the Pi. It won't be. It will just be USB camera with processing on the Pi.
The interface to the odds calculator, and web tracking of game state needs to be well thought out. This is because the remote player will need to send their data to it, as will the QR reader.
I don't think that the QR reader on its own will deserve a single group member. This will mean 1. setting up a library, and 2. getting the QR code out and mapping it to a card. I expect this will take 1 week to interface with the camera from the pi, and 1.5 weeks to interface with a QR library (opencv likely provides this relatively easily). I think you need to rethink work allocation.
Learn markdown, please. The format of plan.md should properly render lists, headings, etc...
A few comments: