Data tables to run IRRs on external data sources

So the short question - do data tables still work if it would involve recalculating IRRs from external data?

I'm using a data table to swap out external references used by the worksheet to generate a range of different values. Example attached to illustrate the structure (obviously ignore ref errors). While the approach works fine for simple calculations, I get unusual results for IRRs, some of which are correct, most are not. Its almost like the data table function only runs through a limited number of cycles, similar to iterative calculation, before showing an incomplete result (it does return values, normally negative and varying in size - its definitely calculating something!).

I thought I'd found an efficient solution for dragging in large numbers of datasets (bear in mind I'm using more than 200 external sources), running various calculations, and then tabulating them. But if I can't get IRR to function, I'll need to do a full rethink.

I'd welcome feedback on this problem!

Also, I know this task requires something more powerful than Excel - that's a longer term project!

My bad, there was a data table referencing issue with my original workbook, this function does indeed work!