“the original paper suggests the lower defining point, 0 °F, was established as the freezing temperature of a solution of brine made from a mixture of water, ice, and ammonium chloride (a salt).[2][3] The other limit established was his best estimate of the average human body temperature, originally set at 90 °F, then 96 °F (about 2.6 °F less than the modern value due to a later redefinition of the scale).”

That’s from your link. Seems like the guy you responded to was correct or the wiki isn’t.

For people wanting to not Read: freezing and boiling were intended to be 180° apart, or the opposite sides of a circle. So a gauge using his scale would have one degree of temperature equal one degree of rotation.
For set points, he used his best approximation of average human body temperature, and the coldest stable temperature that could easily be replicated, which was a freezing brine solution whose temperature would self stabilize. What he set those set points to was based of the work of an older scale, that he adjusted to get rid of fractions and make more fine tuned.