Can he? absolutely
Will he? I doubt it
Conor tends to have hands down while stalking the center and getting his timing down. He will need to get his hands up to defend punches of course but I suspect with his hands down style it will be harder for Siver to land that kick.
Siver is all loaded, stalky muscle and goes from a set-up punch to a kick or spinning kick instantly. He is very good and very quick. Conor however, has insane reflexes and I just don't see him getting caught with it.
I think he should be more worried about being taken down and how he can handle himself with a short, stalky, insulted German with nothing to lose on top of him