Windows 10 remove hidden attribute from disk partition

[Penguin58]

I have a 2TB seagate NAS drive setup up as 1TB mirrored. One of the drives went out but the second one seems ok. Hoping i could recover at least some of the data, I purchased a SATA / USB adapter (suggestion from Seagate support). I am able to see the Disk in "Computer Management / Storage / Disk Management" but when i right-click on the partition, all options except "Delete Volume" are grayed out.

Using DiskPart I select the Disk and Partition but when i enter Detail Partition, I get the message "There is no volume associated with this partition and the Hidden attribute is "Yes"

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DISKPART> detail disk

ST310005 28AS SCSI Disk Device
Disk ID: {9A5B132C-C9D8-4419-941D-C73B93E78950}
Type : USB
Status : Online
Path : 0
Target : 0
LUN ID : 0
Location Path : UNAVAILABLE
Current Read-only State : No
Read-only : No
Boot Disk : No
Pagefile Disk : No
Hibernation File Disk : No
Crashdump Disk : No
Clustered Disk : No

There are no volumes.

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DISKPART> detail partition

Partition 4
Type : a19d880f-05fc-4d3b-a006-743f0f84911e
Hidden : Yes
Required: No
Attrib : 0000000000000000
Offset in Bytes: 2773000192

There is no volume associated with this partition.

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Does anyone have any suggestions?

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