I've heard it's getting more and more common for companies to not test for weed because it's so prevalent. Thins out the labor pool too much! So, they have dropped weed from the profile of drugs they screen for. Not sure if that might apply for you or not.
There are ways around tests but I'm retired and not up to date. Back in my union negotiation days I attended a few seminars on drug testing. I can give you a good 30 year old debate on both the Pro's and Con's of drug testing. Sensitivity vs. selectivity. Etc.
Back then the one best piece of advice on beating urine tests I heard was to contaminate the sample with protein. The easiest and probably most explainable way, as well as readily available, being a drop of blood. Good reason to always wear your union pin. Always good for a finger prick when needed.
Anyway, not sure if that works at all anymore...