"Your honour, I think you'll find that someone broke into my house and planted drugs"

This type of logic has been used plenty in court, it being in your possession, digital or not, is sufficient.

The claim here is that due to the vulnerabilities Cellebrite has, the offending item may never have been on your device. This is more similar to saying that the images the police took in your house of drugs were kept on an unsecured server, there are recorded vulnerabilities for it, and therefore the images could have been digitally edited to show drugs where none were present.