Okay, actually I reread the article again, turns out I wasn't fully paying attention the first time. Sud Ouest even had a frame paragraph at the end of the article showing that the fact isn't indeed related to the match:

The evidence gathered points to an individual action unrelated to sporting results. Witnesses are being interviewed, technical investigations are being carried out, particularly into the telephone system, and the city's CCTV footage is being analysed.

So you were correct, sorry for the confusion.