Sorry to say, but I have seen inconsistencies like this too. I don’t think the cable test can always be trusted. I can’t be certain but I feel like I have noticed mostly with short lengths. If your fluke shows good and non CRC errors than I think you are good. I suppose there is a small chance the error could be in the physical switch port if you still have errors after changing and validating cable.
I've also seen strange reports from the Meraki cable test reporting bad results from multiple different brand new cables. If you're not getting any CRC errors and the sync speed is what you expect, I would leave it be.