Gvozdyk is really fucking good. I think he's the man in the division. Dude is a beast. I wonder who his opponent will be, though. I'm not expecting anyone in the top 5 because they all seem to have fights lined up (or wouldn't fight on this short notice): Browne, Alvarez, Kovalev, and Bivol all have fights lined up. I don't think Beterbiev has anything set up, but I really doubt his team will put him up against Gvozdyk right now. Kalajdzic would be a great fight for Gvozdyk. A very good fighter that pretty much got robbed by Browne.
Kalajdzic - Gvozdyk is a great idea. I would be a lovely clash of styles.
Problem is, thanks to that robbery, Kalajdzic has been fighting B-level guys, instead of honing his world-class skills. Getting screwed can also definitely affect your desire to train at world level.
A shot at Gvozdyk could well bring him back to top form, but of course he'd also be jumping into shark infested waters. The main thing I'd want to see is enough time between the signing and the actual fight. Give him enough time to prepare.