How could I get that wrong? I knew it was instr., must've been a typo (now corrected):
On the DE keyboard I get ą and ę by pressing [AltGr + Shift + ´] followed by a or e - plenty of scope for error there.
Or maybe the situation was just too embarrassing [cf. Leonard & Mrs. Latham in https://en.wikipedia.org/wiki/The_Big_Bang_Theory_(season_4), ep. 15].