I suspect this is exactly why the CEO reached out to you in the first place--because they know how hard it is to get open and honest feedback from the store and retail managers.

Whether the district manager liked it or not, they absolutely would have had to report the results of your visit back to the CEO. And they would have had to be honest about it, since they knew the CEO could just call you back to check the accuracy.

I don't blame you for not wanting to get in the middle of that, but I bet the CEO felt like it was a missed opportunity.