Solve my brother's problem QUICK

[Jspeedy]

My brother is going to be tested in 7 days because he is trying to get a job for a military magazine. This is a test that WILL BE MONITORED. HE DOESN'T FEEL COMFORTABLE WITH USING A WHIZZINATOR. What's the best way for him to clear his piss within this time period or use something to cover it up that can be undetected? Money's not a problem.

[yoda]

i know ppl wo drink about 2 gallons of water before they go in, and it works for them.

[Jspeedy]

i know ppl wo drink about 2 gallons of water before they go in, and it works for them.

But they can tell it's diluted.