Harriot, of course, could see the truth. Unlike Eclipse, the poodle did not have its abilities sealed - it was merely not as strong as Eclipse. At most, it was a little stronger than the average Dao Lord.
Still, that was more than enough to see through Lex and everything about him - as well as the fact that he had random pieces of information hidden from view or obscured even to Dao Lords. Considering he came from an organization that also had a Dao Lord, that wasn't too surprising.
But Harriot did not need to learn Lex's secrets. He could see Lex's intentions in the garden, which weren't exactly altruistic, but they weren't the worst either. His greatest ambition was merely to use some of the resources in the garden, and maybe establish a connection with Eclipse.