You're right on most of that but off on some details.
Only Vyvanse is anti-abuse, because the dextroamphatamine is bound to a lysine molecule. The body must cleave the lysine before it becomes active so snorting it doesn't give the instant rush.
Adderall has no such countermeasures. You're probably getting confused by the fact that it comes in both IR and XR formulations (instant release vs extended release). So if someone has XR adderall, it's not as snortable as IR. But it's still more snortable than Vyvanse is, and you can just get IR adderall which is totally abusable. (BTW X milligrams of XR is really just X/2 mg instant release and X/2 mg delayed release beads that take on average 4 hours to activate. So it's roughly equivalent to two X/2 mg IR doses split 4 hours apart) And finally the XR can be countered by crushing the beads up, although it's a bit laborious.
Amphetamine obviously has its risks, and particularly when prescribing to children doctors seem to write some ridiculously high dosage prescriptions without fully understanding what the drug is like. But you can just say that rather than doing the juvenile "it's really just meth in a bottle" shtick when there is literally already actual meth in a bottle that you can (with great difficulty) get prescribed. And that fact - that methamphetamine exists as a drug that can be prescribed - is much more interesting and surprising to people, given that the lay public is completely unaware that methamphetamine has any pharmaceutical uses.