short answer:
cut the bananas off and strip the insulation back and use bare wires if it is a push button opening affair.
I own a pr of speakers with push buttons that open so bananas can be pushed in from top or bottom, but not open enogh for two conductors to fit in well. bummer if that is your situation..
otherwise:
I’ve used bi wire spkr cables since, forever. some of these cable makers construct their bi wires so one half is tuned to the upper end, and the other pair is for the lower end drivers.
I’d spend tthe 10 or 20 bucks on adapters to get both pairs onto the speaker binding posts if it were me.
this is of course with the understanding those banana plugs don’t unscrew any so the other pr of spkr wires can be fit into the slots made available as the plug is unscrewed.
why bother?
1 as said, you’ll have a better conduit for the signal with more strands attached.
2 they might just be ‘tuned pairs’ aimed at or for specific regions or drivers on the loudspeakers.
3 no one wants to deal with a shorted out amp because wires were crossed or grounded to something somehow.
if you just like to see dangling active wires then cover them up with non conductive stuff as they are ‘live’ and a possible serious problem waiting to happen. kids, pets, vacuum cleaners, etc.