I previously worked in agricultural research (in the private sector), and we spent YEARS trying to replicate some published research from overseas. And that was research that had previously been successfully replicated, and we even flew in the original scientists and borrowed a number of their PhD students for several months, year after year, to help us try to make it work.

We never did get it to fully replicate in our country. We ended up having to make some pretty extreme changes to the research to get similar (albeit less reliable) results here.

We never did figure out why it worked in one part of the world but not another, since we controlled for every other factor we could think of (including literally importing the original team's lab supplies at great expense, just in case there was some trace contaminant on locally sourced materials).