So people are pretty willing to go and join
@EarthScorpion in welcoming Gregor Leon, Agent of WARCRIMES (you could probably backronym it to something. World Assimilation, Re-Education, Conquest, and Repression Institution for Mass Extrasolar Summoning I guess) back for... probably not that long because Cross, as mentioned, has DSci 3.
In fact, his original spheres were Time 3, Life 3 (favored), Dimensional Science 3, Mind 2, and Forces 2, with Enlightenment 4. Of course, he survived Moscow, so that's worth some upgrades. He is currently Enlightenment 4, Time 3, Life 3(f), DSci 3, Mind 4 (Tactical Operations), Forces 3, Correspondence 2, Matter 2, and Prime 2. All in all, he's not exactly Donald or Rose. He's still a better mage than either Piero or Maria. But he invested most of his XP into more augmentation and physical stats and his newfound rank and ludicrously high requisitions rating. What, you think normal people have Ghost Bullets?
Accompanying him is Major Jane Clarent, who is Enlightenment 5 and has the spheres Correspondence 4 (Multitasking), Mind 4 (Brute Force), Matter 2, Forces 3, Time 2, Prime 3. She is rather more powerful as a mage. As you might remember from the car chase, she can practically make any hand weapon dance. Or, to be more literal, make a single bullet ricochet through a room and kill a half-dozen people.
Remember that he
is also backed up by a bunch of Damage Control and THOR agents, who can be assumed to have access to Enlightenment 4, sphere 3 effects in any sphere.
As far as the trap Rose has found herself in goes, it's literally what you've taken at face value. The URTURN system is self-destructing, in a way designed to destroy most of the evidence here. If Rose tries to use her DSci 3 to get out of that space, there's some modifications to the local spatial conditions which will dump her rather deeper into the Umbra than expected... which is perfect for an attempt by Control to eat her and use her as a finger puppet.