My fiance got arrest a week ago for a failure to appear for 2011 but he did time and even got a public defender and released on bond but when you look in the public index it only shows up a charge that happened in 2005 but got dismissed. I don't understand why there was a warrant for a failure to appear.
It is hard to know exactly what happened based only on what you know. What seems most likely is that he was released on bond but didn't go back to court when he was supposed to. Many US states do not publish arrest records, so it not being available to you via web search doesn't mean much. It is also possible he was issued a summons via mail, but his address had changed so he didn't get it.
He will know what happened when he is arraigned. That usually happens within 72 hours.