This "Final Award" document is curious in more ways than one.
Firstly, although the case is USADA (claimant) v Roberts (respondent), it always puts the latter's arguments first, which is not the normal order.
This then seems to have the effect that, in the mind of the arbitrator (going on some precedents albeit) that the respondent has a very low bar to reach, namely that merely a vaguely plausible story that USADA can't rebut (perhaps even for lack of discovery/evidence) is sufficient. One could contrast the Tate Smith CAS case (Australian canoeist), where they didn't accept such shenanigans (he essentially claimed to get stanozolol in his system from the Danube, and they quibbled over whether this was a "bare possibility" versus a "probability").
Finally, the writing is not clear exactly on the facts, but Salazar's story needs some vetting. Even something as simple as: "did she go to India?" doesn't seem to have any facts (airline receipts?) cited. Was her alleged stepfather really there? Etc. (She claims to have "Googled" moxylong: any browser history given?) In any event, her claims about his conversation in Hindi with the shopkeeper would seem to be hearsay. Admittedly, from the Western standpoint of law it's the "opposing's side" to raise these cross-examinations, and USADA here did not (for whatever reason).