For me, it's too early for any bold claims but I don't see it going away quietly. It's weird, the mercenary wars of the 60's and 80's - some of them were rather silly proxy wars between USSR and USA (Nigeria was a total mess), but lots of them were USSR backing great communist leaders like Lumumba who had the peoples support.
In this case though - the coup is originally anti France, anti colonial, it goes forward, and then they decide to brazenly wave the flag of the West's greatest enemy (Russia). It's not like there's much of a material gain for the actual lower class people in Niger in getting Russia involved (unlike in the 60's-80's). It's just the top brass, companies, and governments of the coup's leaders that will get a fat payout and continued guns n armour. What guns and armour does Russia even have to trade with at this point though? They're already at war.
What the fuck is going on? Is it too stupid to say that the top dogs in Niger are now deliberately inviting a war against the West? Is it that they thought war was already going to happen, so they're getting all the backing they can to try to scare the French from striking back?
Could this end in an absolute NATO 'peacekeeper' goatfuck?
My take on the flag waving is that it's a deterrence, basically saying to western intelligence agencies that if you or your paid cronies try to start shit, you won't be facing unarmed peasants but several thousand heavily armed Russian mercenaries with a support base you can't drone stirke, that's enough to prevent any western personnel from touching down in the country itself, even the psychopaths of the Special Activities Center don't want to get in a shootout with former spetsnaz
This is announcing an insurance policy against any potential western counter-coupers
All in all this is a net positive
''My take on the flag waving''
Tbh Russian flag waving by Africans is relatively better than Ukrainians waving Death in June or Buddhist flag/insignia