With no means to produce either food or revenue, and with hoards of displaced persons organized into what I'd guess are autonomous gangs; a small army with light armor would run it's ass ragged trying to keep up with one provence.
The place is a loss and I'd personally doubt that SA can me saved over the next couple of years.
If you mean that the collapse of Zim cannot be halted - I agree with you. But they will have to rebuild someday and the sooner they get rid of Mugabe and his cronies, the better. I agree with you about SA too.