The spring loaded pin is described by Partner as a "safety feature", in that the hose can be unscrewed safely even if the propane supply has been left on.
Unfortunately, it's only one of a few unique elements of a Partner hose and its connection to a Partner stove.
The other elements are the extremely high pressures a Partner stove operates at, and thus the need for a much higher flow of propane, and at a much higher PSI than any typical portable device propane hose operates at.
The online buzz (easy to search for) indicates that a normal propane hose, regulator, and connection can't supply the propane at a high enough pressure, or a high enough flow rate.
The Partner supplied hose is also a crimped and soldered connection, so "reusing" the connector might be a challenge (or impossible?).
Because there is more than one thing going on with the Partner Stove designed and built supply hose, you (like many of us with Partner Stoves) will very likely be obliged to have Partner Steel themselves build you a new hose. At least an advantage to having them build you one is that it gives you the opportunity to ask for a hose of a custom length ... something the rumour mill indicates Partner will in fact supply to you.
I suspect that, in the end, any sort of disassembly/reassembly of an existing Partner hose, along with the cost of whatever new parts might be required to manufacture a "new" propane hose, and the fact that propane hoses with pressure crimped fittings require specialized knowledge and custom equipment to build would make any attempt to have a shop disassemble your old hose, and then "build" you a new hose more expensive than simply buying a new propane hose from Partner Steel.
Personally, I don't see the need for the proprietary fitting, as I'd never leave my propane "on" when assembling or disassembling my stove at camp (even accidentally). But that's how Partner Steel has done their propane hoses and fittings for years now, and I seriously doubt they'll change anytime soon.