My kids were at Taylor Swift on Friday night at the Linc and had no issues parking. They said it was very organized. I think you should be fine.
that's the approach, IMHO. I've never had a pre-paid parking pass for any sporting event, or any concert event, that I've attended at Citizens Bank Park, Lincoln Financial Field, or the Wells Fargo Center. And I've never had any problem getting a spot for the aforementioned at the aforementioned. They (and their parking lots) are right next to each other (comparable to Beaver Stadium, the BJC, and Medlar Field at PSU), and typically the lots for each are open for big events, so you can pick where you want to park. Plus, there are private lots on the periphery (my favorite is the Novacare Complex parking lot).
I wouldn't pay for a secondary market pre-paid parking pass for a concert event at CPB. They're just not worth the prices I saw quoted when I looked them up, and you'll have no trouble getting a spot when you arrive without a pre-paid pass.