Yes, feigning ignorance often helps to solve these issues. CX staff are generally pretty good about wanting to solving problems so they would in general prefer to take longer to solve the problem rather than having to give you unwanted news. ^

I've found in many cases that airport staff have been able to handle weird interlining arrangements as a matter of routine (i.e. no questions asked) that I have been informed by telephone staff that are not possible to interline. This includes interlining from CX to another Star Alliance carrier, when both flights were on different tickets. I just turned up at CX F checkin in HKG and gave them my CX ticket and AC ticket and told them I am going to YYZ (AC) via YVR (CX). Not only did they interline the bags but gave me an AC boarding pass for the next flight too!