Operation Flashpoint: Dragon Rising HELP NEEDED!

I feel so stupid, but I just cant figure this out... any OF:DR pros out there? (probably dont even need to be pro, just not newb)

In mission 2 co-op multiplayer I need some C4 to blow up the missle. Well, in my group there is NO engineer!? So how do I blow it up?

I my co-op partnertried to choosean engineer fromdifferent group, one with an engineer, and I tried to become leader of a group with an engineer but it just wont let me for some reason. I can only choose a recon group or something like that with just the leader, medig, gunner and sniper.

I'm so stuck and I just cant figure out how to blow that up.

(Hoping someone comes along who knows something)

You blow the air defenses with artillery,But use the "scattered" method when aiming though.

Humm I thought sure I hit the Y button there before to see if I had that option.

I guess I'll double check now that you gave me that info.

Thanks!