There's really nothing you can do about worm holes. I have filled small ones in walnut with tinted epoxy, but those are pretty large there.
Yes, the slab can be re-sawn - if - check with the sawyer depending on the mill it may not be long enough. You can book match the two sections to make nice table. I suggest you put the them in stickers and allow them to acclimate for a while (1-2 months) before milling.
On the twisted slab, again, not much you can do about it. My suggestion is to simply break the slab apart in two along the fault line, then you may be able to dress the two boards into usable lumber.