Just ran through the Skills were not active, couldn`t roll dodge and I could only attack. Some of the bosses were still moving around even though they were dead.
I ran this dungeon today and had none of these issues. Were you lagging/having high pings? I sometimes have mobs/bosses rubberbanding around or have skills not fire when I am having lag issues.
I'd suggest check out your latency in-game or if that's not only a dungeon run but a reoccurring issue try console command tracert to eso ip (can Google your server's IP, it's there can't remember it by memory).
If perchance you are using the Dressing Room mod then that might be the cause. Sometimes when I use it it freezes my skill and I will have to use /reloadui to get them working again.