I, too had my seats suddenly start deteriorating. I've recovered them with new skins I ordered from Thor. It cost $500 for both front seats. Call Thor or any Thor dealer to order. I think it was worth the money to not have the eyesore and constant irritation of looking at the old ones.
I considered using discountvantruck.com but chose not to. The cost would have been three times as much, I would have to dispose of the old seats and other than the skin, my seats were just fine.
FWIW, the Flexsteel rep was quoted as saying "Just a side note, if your motor home is a Damon/Four Winds/ Monaco/Fleetwood/Tiffin…..they all had problems with the fabric they selected." So there were several manufacturers who had this problem. I believe all these manufacturers were sold an inferior product without their knowing it was junk. Hopefully the vendor, whoever it was, is now out of business!