Think you are getting your Wookiees mixed up.
Zaalbar was the Wookiee in KOTOR, & Hanharr was the Wookiee in KOTOR2. Bowdaar is new to us, though he does reveal that he is quite old (how old exactly escapes me at the moment).
It's worth noting that Wookiees do live a long time. Wookieepedia cites their life cycle at around 600 years, Chewbacca at the time of his death was at least 210.
So yeah, there is a chance we may yet run in to Wookiees from KOTOR 1 & 2, but Bowdaar isn't one.