I looked back through the transactions posted at the official Phillies web site and can find only the following two for Muzziotti last season.
3-25-21 Philadelphia Phillies placed CF Simon Muzziotti on the restricted list.
10-4-21 Philadelphia Phillies recalled CF Simon Muzziotti from Lehigh Valley IronPigs.
I do not recall when Muzziotti arrived in the US and I do not know how the restricted list works. Is there a period of time to work back into shape/rehab after being on the restrictive list? There was never a transaction optioning Muzziotti to Lehigh Valley. The October date is when everyone on the 40 man roster were consolidated into the 40 man limit, including those on option to the minors and those on the IL, including the 60 day IL. Perhaps Muzziotti was at Lehigh Valley as a part of working back from the restricted list.
He did play 20 games and had 71 at bats, but that was spread over five minor league teams (GCL, FSL, SAL, EAS, INT) which is more in line with the pattern often seen in a rehab assignment coming from the IL than an actual option to a minor league team.
Regardless, even with 2 option years, he should have enough minor league time to either make it to the majors or become a failed prospect.