
The thing about AMOC collapse is that its partially triggered by Greenland glaciers melting so this would be something that would be irreversible. Even if we got all CO2 back out of the atmosphere it may not restart. Then we would be in a situation where big parts of Europe would be against carbon neutrality or reversing climate change, because it would make Europe even colder.
Not a mathematician but the way I understand it, is that it merely shows that there are unprovable problems, not that nothing can be proven.