And KL does make it difficult to ever see the class of service if booked direct through them. See this summary of an upcoming trip from the KL www site. This is for the LAX-BKK $~2100 deal. I purchased through Chase Rewards and have a receipt that shows Z class for all 4 legs. And I used whatsapp to send the PNR to KL and confirm that all legs are in Z -- within the 24 hour cancel w/o penalty period.
I just requested a copy of the e-ticket from the KL www site to be emailed.
Maybe the fare class will appear on that. But it doesn't. Ticket number, non-refund language, but no booking codes.
I get excluding ultra cheap fares from earnings, but just think it should be up-front knowledge.