I am not sure whether I understand you right but if a reviewer made a point concerning missing or incomplete data it wouldn´t be a wise choice to answer "data not shown".

Nowadays most journals offer a nearly unlimited space of “online only” supplement, so it should be no problem to provide the reviewer and the readers with these data.

Keep in mind that the option to use the "data not shown" phrase is intended to give an author the opportunity to skip data that are generated with standard procedures, represent quality controls or are of minor interest. Be sure that any data that substantiate your results are at least integrated into the supplementary material and avoid that the impression arises that data that are not in line with your hypothesis were not included.

Thank you all.

there are no fixed rules. We use data not shown (despite having a half dozen of supplementary figures) when we need a insignificant support eg. the viability of cells was unaffected by the treatment.

It strongly depends on the point that you want to make in the mansucript. If its a key information you need to show. Else its fine.

Finally its a gamble, if the paper gets done it is acceptable and if it does not get done it is not acceptable (and the reviewers will ask for it again).

So take a chill pill and let your supervisor take the call

On multiple occasions now, our group has included data to address reviewer concerns directly in the rebuttal letter--typically a figure or two to address specific controls; not something that is going to alter the main findings of the paper. These data were not even necessarily referenced in the text (as they were not integral to the main story of the paper). Our thought has always been, if you have the data to include, does it really hurt anything to include it in your response letter to the reviewer comments? By including it in the rebuttal letter itself, you can address the point and leave little doubt regarding your claims.