What do the words "Asham Hu" come to teach us?
Rashi: It teaches us that even after the owner dies or after he receives his atonement from another animal, 1 it remains an Asham, and cannot be brought on the Mizbe'ach as an Olas Kayitz Mizbe'ach before he has redeemed it.
Which he brought between the time that the first one got lost and the time that it was subsequently found.
Why can we not extrapolate from it that an Asham that is brought she'Lo Lishemo is Pasul?
Rashi: We cannot extrapolate from it that an Asham that is brought she'Lo Lishemo is Pasul, 1 since the Torah only inserts it following the burning of the Emutin, and the Korban is Kasher even if they are not burned at all.