Immediately take the affected datastore offline. Every second the ESXi host tries to "fix" or write to the volume, it risks overwriting the very data you’re trying to save.
Since VMFS usually sits on a RAID 5, 6, or 10 array, the best software will feature a built-in RAID reconstructor. It should be able to virtually reassemble the disks even if the RAID controller has failed. 4. Preview Functionality vmfs data recovery software