My thought is that you should fill it up with oil and see if it runs, and runs the same.
If the pan was bone dry, I think the chances are your engine should be given a moment of silence, and then allowed to rest in peace.
But, you never know, fill it up and see what happens. These engines, with their iron heads, are very tolerant of overheating. But there is NO engine that can run without oil.
Sorry to be the bearer of bad news, but I hate to see you messing with the oil pan before seeing if it's worth fixing.
I'll keep my fingers crossed for you, and let us know the outcome.
I empathize. I try to keep cars under my kids, and it can be a real challenge. There are times when I think they need to see how many miles they can get out of a pair of shoes.
Best of luck,
'01 C Class, Six Speed
'84 Euro 240D, 523K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in