blood, and there would be some excuse about why they needed to take a venus draw for him, but foreeveryone el evt's a finger prick. they weren't even running the test on the devices. while i was working there, we only ran seven tests on the theranos devices. most of the tests were being run on third-party machines. >> did ms. holmes know at the time that theranos couldn't do all those tests? >> she, yeah, she knew. >> reporter: of the few tests they were running on theranos devices, tyler says the results were often not accurate. >> at thend ethf o everyone was concerned i wouwer giving patients the right resulting. >> reporter: he approached her later that evening. >> she writes, tyler, these are very serious allegations you are making and she's going to havnee byline. >> reporter: but rather than an e-mail, he received this from sonny. had anyone elsead w me would ha them accountable in the strongest way. you are mr. schultz' grandson. the only e-mail i want to see on this topic going forward from you is an apology. instead, tyler gave his two weeks' notice. he went to meet with his grandfathe