While I almost always agree with DRS, I would be quite hesitant to say Rob is in the clear from developing arthritis for the rest of his career.
I see a lot of high level athletes with moderate to severe osteoarthritis less than 5 years after partial meniscectomy. Sometimes it starts within a year or two.
This is highly variable and the cause of the arthritis isn't always the partial meniscectomy itself (it might have developed due to a previous injury, regardless if part of the meniscus is surgically removed or not). But the NBA and NFL is littered with players in their 20s and 30s with partial meniscectomies and progressive arthritis, sometimes severe.
In this study of NFL combine players, 27% of players with partial meniscectomies already had developed arthritis (average age of the sample 22.8).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5435150/
Kemba Walker is a recent example, multiple scopes for partial meniscectomies and now severe osteoarthritis at age 31. Again, this is not automatically the outcome for Rob of course, but personally I wouldn't be confident that we know any potential arthritis will be confined his post-career life.