How exactly are you trying to do it? My Kylo isn't as fast as yours and I can do it. Here is how I do it...
Only attack Grievous with Outrage. If your cool down doesn't reset for whatever reason, attack one of the other droids with his basic.
Never use Lash Out
When the enrage timer is around 7 or 6 start attempting to retreat.
Sometimes you need to make another hit with Outrage to recharge protection
Sometimes you need to back out and start the attempt over if you can't retreat in time.
Rinse and repeat
It takes about 2 hours by yourself. My guild has 3 people who run Kylo in P1 and it takes about 30 minutes to clear.