though the SIA docs say French R/T only, I heard quite acceptable English from the tower, even if the accent was, err, shall we say, "marked" ...
I think you're misreading the AIP entry. It says that it's ATC. It then goes on to say in the absence of ATC it's Air to Air in French Only.
TWR: 128.925. Absence ATS: A/A (128.925) FR Seulement/only.