Can I assume I am in the clear since I have not received a call from the MRO? I don't want to call HR and ask about the test, ha.
Of course you wouldnt want to inquire about the test results.

Instead, call the HR and ask for your "start date". The response there will clue you in as to whether youre good to go, or if the employer had simply moved on to the next applicant for hire.