I'm sorry OP, but if you can't finish Ifrit alive this is a L2P issue.

Yes, the servers are laggy and what you see in your screen is always 2 seconds behind what the server sees, but once you know this, you can just work around it, like everybody else does.

I actually think SE was fully aware of these issues and the fight is somehow balanced around them. If there was no lag and no animation lock, what would be hard about this fight? Moving out of a fire that takes ages to explode? It would have died within 2 hours of release.