No, they don´t need to be verified, then only thing is that, if they are not verified they just not going to have their BAT transfered to their Uphold wallet at the end of the month. Let say that uphold acts like an online wallet and the one created by BRAVE is only local. Using an analogy, insted of giving you the money personally (an unverified wallet) i deposit your earnings to your bank account and afther that you can use them (your verified wallet) by the end of the month.