Everstone affects Nature, not Ability. And as of X/Y, if the male parent has it's HA, the children have a 20% chance of inheriting, though Nidoran M is a special case with it's gender locking. I don't know exactly where that falls, or if it was coded as if M and F were a single species for breeding purposes.
Specifically to your point, whatever it was that happened, it happened at or before the time you evolved Nidoran M to Nidorino. Nidoran M and Nidorino have the same HA, Hustle. If the Nidorino in your scenario did not have Hustle, it COULD NOT be the same Nidoran M you started with.