The board you have is fine despite its misleading name. It has a MCP2515 CAN transceiver which I'm familiar with and have used in some BMW CAN projects of my own.

No need to worry about Pi GPIO voltage since that has nothing to do with the CAN bus voltage.

There is also little likelihood that you need to tap into the dedicated DME <-> AGS bus as well. What values are you looking to read and use in your display? I can probably help with that.