User blog comment:FairyRaven/Fairy Tail Chapter 416: Tartarus Arc: Final Part, Review and Commentary/@comment-112.198.90.159-20150119172538/@comment-7418318-20150119231451

That's not info, that's speculation.

We saw Jackal getting knocked down, but there is no sure confirmation of his being dead or alive and until Hiro Mashima either draws Jackal (or his corpse) again or says so in an interview or something that won't change.

The line that Sayla dropped about Kyouka being the last of the Demon Gates is also just an indication, since she might have meant "The only one still capable of fighting right now" but did want to be so long-winded or had to stop mid-sentence due to falling unconscious.