Passing a urine drug test - while not being too diluted?

First off, welcome ignorant anti-drug assholes, you're always amusing, ready-set-go~

Okay, so my friend (for real haha, I don't get tested in my job) smokes MEDICAL marijuana with a doctor's rec, and is going to be taking a Urine drug test on either Thursday or Friday and she last smoked MJ on mid-Monday, right before she found out about it. She is going to be drinking a ton of water, exercising, sauna, etc.

I understand that the most efficient way to pass in such a short amount of time is to burn as much as fat as possible (and not eat fat until after test), and to dilute the urine to get the MJ metabolites below the "positive" level in the urine.

**MAIN QUESTION**

**Must answer this to get "best answer"**

HOWEVER a lot of things are also saying the labs LOOK for heavy dilution and may throw it out for a retest (which is fine, giving her more time) or they may just call it positive just because its so diluted. Taking vitamin B helps because it makes the pee yellow (when it would have been clear) however, is there any other tips, things to eat or drink the night before and morning before the test? In order to not have the pee so diluted and pure water liquid, but that won't get in the way of the metabolite dilution?

Thank you so much!

This job will mean the world to her if she gets it, and medical MJ in no way impairs her ability to do the job, so it sucks it always comes to this... for now that is, for now ;)