Ade I'm just shaking my head. Once you start with saying "lpmm" is not the same...
Add to that both teams were using ISO certified charts.
What is it that's hard to understand?
Some charts have markings to 2000 lpmm. Others have much finer markings to 4000 lpmm. Obviously, 2000 is not equal to 4000. And yet other charts have no lpmm markings at all. Not to mention in the digital world, lpmm is a less meaningful metric anyway due to differing sensor sizes.
And how does one know that "both teams were using ISO certified charts"? ISO does not certify any of these charts! You can print your own ISO chart using an inkjet printer. Is it certified? No. Can you compare its numerical lppm results to an ISO chart printed on photographic paper? No. Is one more more valid than the other? No, they are just different. Neither are "certified", and "lppm" results will NOT come out "the same" between them.
Not to mention that ISO target designs are relatively old, and we have better designs now for computer analysis. Imatest recommends SFRplus charts for use with their software.
I've seen the Photozone test chart and it doesn't look like an "ISO chart" to me (and no lppm markings, anyway):
I've explained how factors such as shooting distance and lighting will affect the results of these tests (see Imatest's test procedure for example.) I've also mentioned that both sites are likely using two different metrics (lines vs. line pairs).
Ignore any info as you wish.