They say his name in a pink, heart-shaped speech-box, and it seems odd for them to flirtatiously mess with one telepath for the express purpose of flirtatiously messing with another telepath.
But you're still right. They explained their motive (somewhat) in #2 so we have to accept that at face-value until/unless it changes.
The subplot with Emma and Scott suggests that there may be something more to it though (like maybe one of the Cuckoos develops stronger feelings) but maybe not. The series is already a little disjointed in having Cable apparently date 7 different girls between 2 issues, so maybe he'll be with someone else by #3.