In the military, we have a very easy solution to such “mysteries”. Urinalysis. Test every person with access to the space where the drug was found. If warranted, we would conduct a “command sweep” where every single sailor on the ship was tested. It’s too late by now, as the drug would be cleared by now. I guess the problem would have been the large number of positive tests for various drugs, disqualifying those people from holding security clearances...