Nice to read some of the responses above and start the morning with a chuckle .... I hope the OP has a sense of humor.
I must admit, I wasn't familiar with 2 of the 3 places your father wants to go (CLL and SBN), so I had to look them up. He wants to go from College Station, Texas to South Bend, Indiana .... via Beijing?
Is he flying business (or first) or coach? If he's trying to do this on AA/OW, then it makes a difference to which airlines to use or avoid (e.g., no BA or CX if it's a discount coach ticket, if you want miles).
Problem 1 - AFAIK, AA only flys to DFW from College Station, so I guess that pretty much sets the first leg.
Problem 2 - AA doesn't fly to South Bend, so I guess he'd have to go to ORD.
CLL-DFW-LAX-PEK
LAX-PEK is an AA codeshare on China Eastern Airlines. Far, far better to take CX to Hong Kong and on to PEK but you can't do that on 3 legs ....
No OW airline files Beijing-Shanghai, so to get back, it's either the China Eastern flight to LA or back to Hong Kong.
As someone else said, he could do a RTW ticket but the trip is really point-to-point.