I see some partner PNRs on award flights I booked on co.com or (new) united.com: AC, LX, NH, OZ, SQ. Even the VS PNR that I had to give up due to schedule change around the time they ceased the partnership. Very funny
But no LH, TG or QR. I understand QR but why not LH
Unfortunately I couldn't use AC or LX PNRs to change my seats on their websites...