Ok, that makes sense on my ticket, so if I have liquor in my bag then it needs to go to CAI and recheck there. I've only flown QR into CAI once, but definitely had my luggage delivered quickly that time. (priority tagged of course) Other experiences with RJ and EY less impressive, also with priority tags. I guess I might need to start a thread about average QR times to get luggage on priority tags in CAI.

For point 2, it seems from that thread seems it's quite likely they'd agree to through check onto JL, so we should be able to put 2L in that bag and send to Japan. If they push back I'll even mention there's liquor inside that we aren't legally allowed to take into Qatar I guess.

I find it quite odd and frustrating that Qatar doesn't allow at least 1L like other muslim countries that allow controlled sales of alcohol like UAE, but c'est la vie. You're welcome to buy it in a hotel bar at a high tax rate, but oh no... can't bring 1L in your luggage. Very frustrating.