Same issue here on Pagle, no voucher, thus no follow up quest to get the stein 
Here I am on day 4 of Brewfest and the issue still hasn’t been resolved.
Not getting it here on Windseeker either.
Was able to get it now on Mankrik. the guy beside ram racing had a quest, turn in at the guy you redeem your tokens at in the brewfest camp
Confirmed to be working on Grobbulus now. Quest giver next to the ram race npc.
Thankfully they added it!