That's one of the potential problems that Salazar will face. CAS could decide that he deserves more than the minimum punishment for that, say 5 or 6 years, but they can't decide on a lower ban for that violation, as explicitly spelled out by AAA.
The fact that Salazar appealed and not USADA does not imply that the ban cannot get extended.
CAS could also use the presence of the two other violations to impose a higher ban for the testo "experiment".
CAS could also rule differently on the two additional violations alleged by USADA that AAA didn't not consider as proven despite USADA's evidence.
Finally USADA could also submit new damning evidence, or submit the old one they originally submitted too late to AAA to get considered.
See for example here:
https://www.telegraph.co.uk/athletics/2019/12/07/alberto-salazar-witnesses-had-death-threats-not-testify-reveals/