Pick up the price of the gas and if I am off that day, I can pick you up at the airport and take you to Youngstown. It would be helpful if all 3 of you arrive at the same time. But as you mentioned you have family and friends here so perhaps they can assist too. It is not all that far to Youngstown and easy to get to by car. I have a bike rack here you are welcome to use if friends do not have one.
Also I live very close to the airport so if you wanted to collect here to start the trip, you are welcome. It gives you the option of some people grabbing a cab. Maybe $25 to my place (if you need to all arrive at different hours of the day).
What is your intended route? PA bike route A is not too bad till you hit Route 51 in Pittsburgh. The section from Monaca to Coraopolis will be busy, loud and nerve wracking but not overly dangerous. There is a good shoulder most of the way. I would recommend crossing the Ambridge Bridge then cross back to Coraopolis but sadly the Ambridge Bridge will be under construction again this year. PM me or call your friends when it gets closer in, to check on the status of the bridge. It might be fully open by that time or the sidewalk might be open. The bridge would save you a good chunk of the busy section plus a killer hill.
There is supposed to be a
real nice B&B in Beaver. This would be about half way for you. Beaver Falls is a horrible run down steel town but nearby Beaver remains very charming (at least last I have been up there). This would be about half way for you.
Let me know if you have plans to actually ride to the city and I can give you some tips there too. Even if you have to have your friends drive you into the city don't miss
Bicycle Heaven our bicycle museum. Give yourself at least an hour to see because the place is huge.
This might also be an option for your bicycle needs. Craig has literally thousands of bikes. Most of them vintage but he might have a few touring worthy bikes hidden in his stash. Craig is a good guy. Explain your story about you Grandpa and it would not surprise me if he figured a way to help you out.