"The bad German waiter is working at the ninety-eighth restaurant."
Translation:A rossz német pincér a kilencvennyolcadik étteremnél dolgozik.
One more confusing thing: sometimes "étteremben" and "étteremnél" are both accepted, sometimes only the first, sometimes only the second.
"éteremben" refers to the building/place itself, "étteremnél" refers to the restaurant company. Both are acceptable in this case.
I don't work for Duolingo, nor have I got this sentence so I can only speak for the language itself. :D