I think your estimate of how costly it would be to run a replication study is too pessimistic. In addition to the issues that MHR identified, it strikes me as unrealistic that the cost of rerunning the data collection would be more than 10,000 times as high as the cost of the original research project. I think this is highly unlikely because data collection usually accounts for at most 10% of the cost of research. Moreover, the cost of data collection does not scale linearly with the number of participants, but linearly in the number of researchers that are paid to coordinate data collection. The most difficult parts of organizing data collection, such as developing the strategy and establishing contact with high-ranking relevant officials, only have to be done once. Moreover, there are economies of scale such that once you can collect data from 1 school, it is very little effort to replicate the process with 100 or 1000 schools, and that work can then be done by local volunteers with minimal training for minimal pay or free of charge. It certainly won’t require 10000 times as many professors, postdocs, and graduate students as the original study, and it is almost exclusively the salaries of those people that makes research expensive. To the contrary, collecting more data on an already designed study with an existing data analysis pipeline requires minimal work from the scientists themselves, and that makes it much less expensive. Therefore, I think that the cost of data collection was probably only 10% of the cost of the research project and only scale logarithmically with the sample size. Based on that line of reasoning, I believe that the replication study could be conducted for one or a few million dollars.
I think your estimate of how costly it would be to run a replication study is too pessimistic. In addition to the issues that MHR identified, it strikes me as unrealistic that the cost of rerunning the data collection would be more than 10,000 times as high as the cost of the original research project. I think this is highly unlikely because data collection usually accounts for at most 10% of the cost of research. Moreover, the cost of data collection does not scale linearly with the number of participants, but linearly in the number of researchers that are paid to coordinate data collection. The most difficult parts of organizing data collection, such as developing the strategy and establishing contact with high-ranking relevant officials, only have to be done once. Moreover, there are economies of scale such that once you can collect data from 1 school, it is very little effort to replicate the process with 100 or 1000 schools, and that work can then be done by local volunteers with minimal training for minimal pay or free of charge. It certainly won’t require 10000 times as many professors, postdocs, and graduate students as the original study, and it is almost exclusively the salaries of those people that makes research expensive. To the contrary, collecting more data on an already designed study with an existing data analysis pipeline requires minimal work from the scientists themselves, and that makes it much less expensive. Therefore, I think that the cost of data collection was probably only 10% of the cost of the research project and only scale logarithmically with the sample size. Based on that line of reasoning, I believe that the replication study could be conducted for one or a few million dollars.