Can i continue a game in the halo 3 legendary campaign?

Me and my friend were playing halo 3 on the last level of legendary when he lagged out in the middle of the part where you get in the warthog and you drive away. If i start the game from that checkpoint, when we finish the level after i load the checkpoint, will it count that i actually beat the level?Can i continue a game in the halo 3 legendary campaign?
if you start from the beginning of the warthog part, then you should be safe





so, yes, you can do that.





and, you can play with a different friend than the firstCan i continue a game in the halo 3 legendary campaign?
Yes, I'm not sure though but it worked when i did it at my friend's house
if you personally get to the end of a level on your account, then it will.
i think it will, not sure though