^ Elbows and knees can discourage takedowns, but definitely aren't an effective frontline defense. Furthermore, they aren't applicable since he's fighting amateur, in which elbow strikes and knees to the head are illegal.
I do agree, though, that you've got to get offensive. The most important thing you can do when fighting a grappler is to remember that you're in a fight, not a grappling match! You want to try to hurt him all ranges and not accept his game. You should be punching him from your feet, punching and kneeing in the clinch, and even striking from the bottom (of your guard, not from bottom of a dominant position lol).
That being said, you need to have your MMA grappling fundamentals down. Practicing standing up against the cage, using underhooks to stand, framing and scooting out from guard. All of these skills are pivotal for ruining his day.
Its unlikely -- nay, borderline impossible -- to completely avoid a grappling confrontation when your opponent insists on it. But refusing to play his game by constantly striking and disengaging/standing back up (in a technically sound manner, of course) is a great way to break his will.
Easier said than done, though... My next fight is against a wrestler with a good RNC so lets see if I can put my own advice into practice...
btw, how did your fight go? Looking at the date, this happened ages ago.
As your cornerman and trainer you need to focus on the worst possible positions he's going to put you in especially when he has your back. That's what Ebersole trained against his fight against Hallman. Look what happened. By repelling his greatest threat it broke Hallman. Once he reversed the position he put a hurting on em.
Cardio is key. You'll have to put the pressure with feints rather than play defense cuz he's going to come at you. Once you feint he'll try to shoot eventually thinking you're about to "over commit" then you know what to do.
If all else fails...sweep the leg.
Marcus Aurelius: Tell me again, Maximus, why are we here?
Maximus: For the glory of the Empire, sire.
Baked, not fried... the healthy choice.