Lessons of hard times
Its interesting that we would both encounter "hardship" at the same time ... and beneficial for Gabriel ... so he can see, first hand, how we each deal with it.
My approach: to forego any personal luxuries and desires and to make sure I have good credit, so that I can cover the costs of his trip and visit - no matter how uncomfortable or inconvenient it might be. So that he knows that, no matter what, I would never turn him away and he'll always have a place to go. And so that he knows that I would never put myself and my desires before his needs. I openly admit to him that any current or recent financial complications are entirely my own fault and how I intend to make sure it doesn't happen again.
You're approach: send him (and Sage) away, while moving to a new city, forcing him to leave his friends behind and make new ones, because its more convenient for you. Have him return from his visit, to a new home, in a new city, where he doesn't know anyone - because that way is easier for you. Regardless of how it might affect him. Don't include him in any of the decisions. So that he gets to pay and suffer for your mistakes. You blame your financial problems on me, on Michael, on Kristopher, on Apollo - anyone but yourself. And you provide no lessons from it.
Is what I'm saying false? If its the truth then you can't really say I'm manipulating him by telling him such things. Telling the truth is not manipulation. He doesn't hate you because of what I tell him about you, he hates you because of what you do.
My parents taught economics not to speak to strangers.