If the Flyers were going to make an offer including all three of the names included here, it would be part of a package for someone with value like Connor McDavid. (Before people start jumping down my throat, no, the Oilers wouldn't trade him for anything. That's just the kind of return Philly would need to put this many assets of this quality into a single deal.)
There is functionally nothing another team would be willing to trade that would convince Philly to abandon our plans to remake our defense with home grown, top tier prospects.