In exodus, how did the ODST specialists, who are ODSTs and don’t have Spartan III armor, use Jetpacks, which are armor abilities meant for Spartan III’s?
They can’t even use equipment, as evidenced by Halo 3 ODST.
The jetpack itself is considered an armor ability, but it’s not really an armor ability chip like the others like sprint and armor lock. It’s a jetpack. They can just strap it on their backs and there ya go.
That particular group of ODST’s were in the Bullfrogs an elite team of jet pack users.
I guess Jetpack is a bit of a different case than most abilities.
They couldn’t use it before because it hadn’t been invented (first appeared in Halo Reach – chronologicall nonsense though).
I’m ok with the way it is in the campaign. The entire situation with AA’s is hard to explain/conceive anyway, just try to avoid thinking about it. 
I thought AA’s could only be used by Spartan III’s…
Eh, whatever. Just another plot loophole.