I suspect the first thing that any lawyer is going to say is "Try to resolve this within the Brazilian Skiing Governing Body" and then, failing that, within the Brazilian Olympic Committee, and after that via the FIS and it's only after all those roads have been exhausted that the CAS is going to even consider taking the case.
In other words, you will be in for a long fight. I was in a discussion on another board this week about Claudia Pechstein's 2009 doping ban, and as far as I could see from Wikipedia the litigation arising from that is still being argued about & is not fully resolved.