FWIW, it is currently not possible to upload a French
pass sanitaire QR code, or more generally
any EU Digital Covid Certificate, directly into the Apple Wallet. You need an app or a website or some kind of specifically developed support that allows you to do this. I know little about this. Here are two recent sources:
Après l'attestation de sortie, place au pass sanitaire.
Spain this week rolled out Apple Wallet support for the European Union's digital COVID certificate, allowing citizens to store the so-called COVID-19 vaccine "passport" on Apple devices.
As far as I understand it (see comments for the article), in the case of Spain, you cannot scan a pdf file/QR image into the Apple Wallet, you need to load it directly from your national/regional health service into the wallet. Which is only possible for people who were vaccinated/are registered as residents in Spain.
FWIW, I was vaccinated in the EU but not in France and I have two EU Digital Covid Certificates, one for the first vaccination and one for the second. I only needed the QR code for the second and final vaccination for upload into TousAntiCovid.
I guess that you have the most recent version of TousAntiCovid and that you tested the QR code with the TousAntiCovid Verif app?
Please let us know what the app support advises.