2003 Lancer - engine repair question

I was hit by someone the other day, resulting in my driver's side tire being pushed back into the wheel well, damage to the front quarter panel, and some other damages. Due to the tire, the car had to be towed.

When I got the preliminary estimate from the shop today, they included an option to replace the engine. The prelim estimate before the engine cost was $3200. They will know tomorrow (hopefully) if my engine needs to be replaced. Is anyone familiar with approximately how much it would cost if the engine needs to be replaced? (The work will have to be done in Los Angeles.) I'm hoping the insurance company does not total my car, but am trying to prepare for the worst. If they do decide to replace the engine, does that include the transmission? I've been told by one person that it does, and by someone else that it does not, but that I should insist they replace both at the same time, as a new engine would quickly wear out an older transmission (the car currently has ~70k miles on it, it's their 4 cylinder engine).

Thank you so much for any advice you can give me!