Why did it need to be tested three times to get an accurate result
I’ll wager it was tested way more times than that. The lab tried SO hard to corroborate the field test. They tried and tried and tried but just couldn’t do it. Thing is, they tested the honey. The field tester swabbed the outside of the container. It was possibly a true positive, due to someone else’s handling of the container. A store clerk perhaps. All fanciful imagining on my part, but quite likely all the same.
Those screening tests are ridiculously sensitive. Heaven forbid a false negative should slip through. Better to have hundreds of false positives. I once (literally one time) helped a ski patrol carry some avalanche charges. 10 years later I still cannot fly with the day pack used because it still triggers explosives screening tests at TSA.