First off, clarification - I realize I have two separate tickets and not a "connection." Sorry about the improper terminology.
Second, I thought the Manila Hopper was a fully refundable trip, but I must have made a mistake when booking, and see that it is not refundable. That said, we would only be looking to retain the value in a FFC.

I think I'll just cancel it at exactly 30" before departure if we're not at the gate by then. Obviously if we're 30" late or more leaving TKK, I'll cancel it then. I'll have a FSM SIM card and will have data services while on the ground.

Thanks all for helping me think this through.