While I don't have exact information regarding Thomas, I do have a listing of Doty's born in Rennsselear County, NY.This is what I've got.If you'd like more, let me know and I'll email you the entire file, perhaps it can be of some assistance.
JOSEPH DOTY b. Bristol Co., MA1775 m. location unknown1805 wf. CONTENT ch. 1.RENNSSELAERb. Renn. Co., NY1805 2.DANIELb. 3.ELISHAb. 4.Others ?
Because of the similarities in dates and years, I thought I'd forward you this info. Hope it helps!Also, let me know what you've got, maybe we can fill in some holes together.