That is because what buyer B's predecessor (buyer A) did or did not do is relevant. The SOL started when A took title and that time is tacked onto the time that B owned the property. It is called Tacking.I gave you my opinion that your SOL runs for 15 years from the date that the state transferred the land to your buyer A.
Buyer A is not your defendant nor is the county. It is a private person, buyer B. Buyer B did not receive a title from the county. Had your buyer A kept the property and you were claiming against him then the SOL would be 10 years. But that is not the case. Buyer B did not receive title from the Tax Assessor. He received title from buyer A.

