I did transfer 1000 from BA to QR but still don't get any options to use them for part pay. I'd be ok booking separately the trip and Discover Qatar hotels - interesting about booking via BA as Codeshare. I checked the Discover Qatar website and while booking you have to provide the 125- ticket number, would I get that number if I were to book on BA website on QR metal?

Interestingly if I try to book the multi city and I enter my BA Executive Club number, I get a warning saying that they couldn't fetch my Executive Club status. Wonder if that's why I don't see pay with avios option.

EDIT: Trying to find a multi city on BA yields no results