I haven't tried to lay it out clearly, but it seems to me that this node works under the flawed but common (it seems) assumption that there is some one "compile time" followed by some one "run time". Each line of code has one "compile time" and zero or more "run times" and those intermix quite a bit in even simple cases. The CHECK block of one module seems unlikely to be reliably run between the "compile time" and "run time" of some other module.
Without checking (since "perldoc -f CHECK" and other similar attemps to easily find the relevent documentation are likely all still useless), your use makes me guess that CHECK blocks are the ones that get run after the main script has finished compiling. So this would only be useful for distinguishing mundane use vs require from the main script.
So I don't think that addresses the requested problem at all, which is trying to reconstruct whether Some::Module should be reconstructed as having used or as having required each of the modules it loaded.
