WELCOME to these Forums...
New filters can plug up so that is not a big deal... I have no idea what damper you may be needing?
if it is not essential for the operation of the mower, ask them to get it back and let you catch up with mowing while the part is on it's way... They may even have a loaner to keep things going, it sounds like you have a great dealer, not charging for the pickup & return...
PLUS as you said: "Purchased for $4,500 end of may, delivered umay 25" looks like you purchased it at the End of May, but they delivered it Before the end of May, on the 25th...
That is stellar service... :smile:KennyV