Hey guys, I was going about 20 mph when my timing belt blew, pulled over, noticed oil pouring out! I did try to start it two times. My mech, which has not looked at it, says I need a new head due to valves being screwed and pistons might be damaged etc.. One of my q's is where would the oil leak be coming from on a blown timing belt? And can it be determined that a valve job would need to be done?

Looking at a $2400.00 repair without looking in to it first. What direction should I take??? Thank you guys for your help!!!