I honestly don't know how they are going to stabilize the peso just from diversifying their reserves into bitcoin alone. But holding a decentralized store of value like bitcoin or even precious metals could definitely help in the long term.
What's important here is that regular Argentinean people should be investing in bitcoin and hedging against the inflation that is taking away from their real wealth (>30%).
Even in a bear market, bitcoin offers much better storage of value than the peso at this point. And with other foreign currencies not as accessible, it seems like bitcoin could be a good alternative. Not to mention that in the long run, not only will BTC hold its value, there may even be slight profits to be made given that adoption will continue to rise.