Welcome to the forum, can do man.
First, I would suggest that you modify your signature to include your coach and toad information so that other members will know what you have and be better able to help answer your questions.
Secondly, I'm going to take a guess at what you have. You're posting on the Winnebago Owner's Forum and you mention the hex key doesn't work to open the engine cover. On my 2003 Suncruiser I had such a set up so maybe your's is the same as mine was.
The hex key is inserted through the carpeting into a female hex headed bolt. On the other end of the bolt is a cam-like lever that locks the engine cover down. If you turn it all the way to the right, it's locked. If you turn it all the way to the left (counterclockwise) it's unlocked. The bolt should not turn continuously or else something is loose or broken down there. If you turn it counterclockwise until it stops you should be ready to remove the engine cover. You can lift up slightly at the rear of the cover and then you have to pull it back because there are tabs on the front of the cover that prevent the front end from lifting up unless it is slid back.
The first time I had to do this it was hard. The covers tend to get stuck down and glued in place. If you lift at the rear of the cover with a small prybar (make sure the bolt is turned fully counterclockwise) it should pop free. Then you can slide it back easily.
If the bolt keeps spinning, I'd try to gently pry it up and if it didn't go I turn the bolt 1/8 turn and tri again. Keep repeating until you eventually find the spot where the cam is disengaged and it'll lift off when you get there.
I hope this helps.