Like Pilgrimsmaster said, better to ask forgiveness than permission.
Maybe wait some more with the splint. But I reckon you can do anything you want now. If the chip keeps wanting to shift at this point, it’ll find a way to do it eventually no matter how careful you are, unless you’re willing to spend the rest of your life not using your hand.
If it was coated, I’d say give your body more time to anchor it. But for uncoated chips, my gut feeling is that the whole splint and vitamins thing is more wishful thinking than anything else. I mean it probably works to an extent for people whose body reacts strongly to foreign objects, but the anchoring is probably weak or nonexistent for most people.