On the bike of a constant near and far tourer, probably best to replace whatever needs replacing sooner rather than later.
It is however also good to remember that the Rohloff HGB is operated by two pull-pull cables. The cables do no pushing, so their stiffness in compression is irrelevant. All the stress is in tension.
Whatever you decide to do, you have to fix the loose end immediately, even if only with a bit of electrical tape, though Geocycle's tip of superglue is tidier. The danger is that some more of the wire unwinds and starts slashing at your bike's paintwork, plastic mudguards, and any luggage you're carrying.