You're not completely in the doghouse yet; I was in this situation once before and got out just fine. Take your grenade launcher with you, your grenade rounds, acid rounds and BOW gas rounds. When you go to fight the tyrant, as soon as you get control of Claire, press the control panel to send one of the crates at him. Once he recovers, you won't be able to use the panel again until it beeps. In this time, pump as many acid rounds, grenade rounds and gas rounds into him as you can - if you hit him with enough power, the next time you let a crate go, he'll fly out the back of the plane and you most definitely have enough power to defeat him! The only thing you have to worry about is staying out of his reach, it will be tough - very tough - but you can do it, it's possible. (Are you sure you don't have even one herb in your box?)