I agree that it's unfeasible. But... it's fun to consider the concept given that it's a Sunday morning, the only time to really try such a trek.

What if......
1) first class pax, and carefree vacation travelers.
2) close arrivals gate
3) early arrival from LAX (flightaware shows the last two Sunday arrivals at 7:30 a.m. and 8:33 a.m.) Let's say 8 a.m.
4) 15 min to clear immigration and customs (I've done this before, but I have no opinion on crowds at that hour). 8:15
5) PTY to Miraflores Visitor's center, google maps predicts 30-45 min. I'd say 30 min. 8:45
6) 1.5 hours at the locks (not sure if it's open, and be careful of the holidays 3-5 & 10 Nov). 10:15
7) Back to PTY, assume 45 minutes. Can't take Cinta Costera, closed on Sundays for bikes. 11:00 a.m.
8) Immigration and security on a Sunday morning. 30 minutes is very safe, and first class pax can use the Gold Lane. 11:30
9) 10 minutes walk to gate for LIR flight. 11:40

Doubtful that Copa will be boarding a 12:30 flight at that time. Their boarding passes always say an hour, but it's usually 30 minutes or so. If you're in first class, maybe you're not worried about overhead space and could board later.

Of course, the above is perfect timing, and you could hit a snafu with any of these projections above. But you could just take the next flight out, right? Which is at ..... oh, Thursday. Nevermind!