You should definitely send an email to 3DR support about the flipping. I know you feel like you had a bad experience with them (ie. not communicating well), but I have always found their email support to be super responsive and helpful.
For the flipping, they are probably gonna tell you to start with an IMU calibration and then go from there. You may also need to trim your TX. There are youtube videos on 3DRs youtube channel that show you how to do both. I don’t have the links handy, but again, if you email 3DR they will get right back to you - and probably include the relevant links.
P.S.
I had a lot of snow landings this past winter. In every case I pulled the battery, blew out as much snow as possible, then took the Iris+ indoors and placed it over a warm air heating vent. Same goes if you fly in the rain, which I’ve done a few times (not recommended). Before you reconnect the battery, always make sure it totally dry.