This is absolutely a good cop, bad cop routine. The major is getting taken for a ride.
I think it's only half this. Hazen's teaching Yan, but she's still been shown to be pretty distrustful of him, so I don't think she'd so quickly go along with a good cop/bad cop routine like this. I think this is her legitimately trying to "get at" Hazen, just that unknown to her this whole thing is really Hazen's idea. So Hazen had her here and deliberately acted like an asshole to spur her into action, knowing she'd suggest this.
The idea would be to put Szymant into a situation he'd fail in, and also put Yan there when it happens, so when shit inevitably goes south (Szymant throwing a tantrum/whatever), Yan realizes she's better off sticking with Hazen rather than trying to one-up/betray him like this. So Hazen gets the outcome he wants from Szymant, while also getting more loyalty out of Yan.