Welcome To The Corvette Action Center corvettegirl!
I don't know what they could have done when they changed the battery that would cause the hood to not latch, unless they left something lying on top of the battery preventing the hood from closing completely. The hood latch adjusters are in the hood itself and should in no way have been touched for a battery swap.
What procedure was followed when they removed and replaced the battery? Did they take the side "gill" off as they should have and removed the battery that way, or did they remove everything from above the battery and lift it out that way. I saw someone with inexperience in Corvette battery removal do that, and there is much more work involved, than it is if you do it the correct way - through the side.
If they pulled it out from the top, they could have mis-positioned something that now interferes with the hood fully closing.
I don't know what else to tell you but to re-adjust the latches so that they catch and lock.
I have to agree with Ken. Sounds like some one who does not know Vettes took the battery out the wrong way. The hood problem could be a coincidence but I doubt. Bring it back to who worked on it or even better to some one who knows Vettes. Good luck.
It's possible that even if they removed the side gill to replace the battery, they could have re-installed it wrong!
There's shims under the pivot bolts that are supposed to align the gill panel with the drivers door.
If the gill panel is set too high, it could hit the bottom of the hood preventing it from latching. :bash