What are your thoughts on Janoshik’s repeated positive fentanyl findings?

Janoshik says the sample believed to be 5-Amino-1MQ was tested using two different fentanyl immunoassays, with each test run twice. Even after dilution, all four tests reportedly came back positive.
Does this increase your confidence in the findings, or do you think confirmatory testing (such as LC-MS/MS) is still necessary before drawing conclusions?