If you need a viable population of some thousands, how come it has been possible to re-establish animal populations based on only a handfull of individuals? In many cases, they have managed to gather the 2, 3 4 or so living individuals of a kind, make them mate and after a few years they have been successfully re-introduced on their island or in their region and now are as safe as any animal population can be these days.Uh... no.
First of all, there are very few examples of this. It is rare, but possible, in cases of extreme luck, to get a bottleneck that narrow and still have the population rebound. I read about two examples:
Cheetahs and elephant seals. In the case of elephant seals, the numbers were down to around 20, and now they are around 30,000. Cheetahs are pretty much identical genetically, and they went through an extreme bottleneck around 10,000 years ago.
But they are not "as safe as any animal population can be these days". Genetically speaking, they are at a very high risk. One disease for which they are all susceptible and they die out.
So my point stands, most species need a minimum viable population that is in the hundreds to thousands of individuals to survive.
Two individuals is just not possible without sky-daddy magic.