Even if he does want to drug test you whether collection at an off site facility or if them come to your site for collection or if it is an instant test, he still has to follow protocol and that is unobserved pre employment testing or a monitored test if it is a multistall bathroom (a same sex collector stands in the bathroom door way to protect entrance into the bathroom by others or if the water supply to the sinks can't be controlled) unless you give cause.

Practice carrying the QF on you and do it for the first few days.