Help with Disk Utility Error

[chassey4]

am running Mojave 10.14 beta on iMac retina 4K 21.5 inch. the problem shown by this attachment has been a long running one. by that I mean it has appeared on earlier iMac IOS. it appears. when I run MacCheck or tech tool pro. 10 (both Micromat products). it does not seem to affect the computer operation but I'd like to know if it will lead to a serious problem. thank you

 

[Weaselboy]

What do you get if you run Disk Utility First Aid on the Fusion drive?

 

[chassey4]

What do you get if you run Disk Utility First Aid on the Fusion drive?

I get "operation successful"
since I'm running Mojave beta and all else is good have decided not to continue searching for an explanation. thanks for your help