I just did a quick search on facebook on Ikač and Ikáč. Haven’t found anyone with Ikáč surname, but there are plenty of Ikačs
Eastern Slovaks generally don’t use long vowels neither in their spoken language nor written, except maybe interjections or in songs.
I don’t know about Rusyns, but I think it’s the same.
Do Serbs and Croats write acute accent marks?