I've got two backup drives that I run out of the same enclosure and they both got screwed up somehow. Maybe the enclosure didn't get shut off properly at some point. One drive was fixed automatically on booting by Windows CHKDSK. The other drive can't be accessed by Windows, it just asks me to format it. The partition shows up as RAW but it should be NTFS. I ran Testdisk on the drive using "Deeper search". I identified the system reserved partition and the main NTFS partition, but Testdisk can only access the file list on the system reserved partition. The boot sector is fine, but Testdisk says the MFT and backup are bad on the main partition:

ntfs_boot_sector
 2 P HPFS - NTFS             70  29 24 243201  45 44 3905900544
     NTFS, blocksize=4096, 1999 GB / 1862 GiB
NTFS at 70/29/24
NTFS at 70/29/24
filesystem size           3905900544
sectors_per_cluster       8
mft_lcn                   786432
mftmirr_lcn               2
clusters_per_mft_record   -10
clusters_per_index_record 1
Boot sector
Status: OK

Backup boot sector
Status: OK

Sectors are identical.    

MFT and MFT mirror are bad. Failed to repair them.  

However, when I run GetDataBack on the highest level, it lists my files on the partition:

CAPTURE 8/1/2020 11:52:16 AM
File System Properties
File system: NTFS
Size: 1.82 TB
Location: Sector 1,126,400
Cluster0: Sector 1,126,400
Cluster size: 8 sectors
Phys. sector size: 512 bytes
Total sectors: 3,905,900,543
Total clusters: 488,237,567
Data matches/rel:120649/22
Source details:B@1126400BB@3907026943
Source: B2
Recovery tree:Tree NTFS, 812171 entries
Total files: 769,963
Total directories: 54,566
Total file size: 1.55 TB
# dirhash entries: 812,171
MFT cluster: 786,432
MFTMirr cluster: 2
MFT size: 1024 bytes
INDX size: 4096 bytes
# Mft:0
Explicit Mft no:True
Area: Ambiguous
Created: 

I'm wondering if there is any way I can leverage the information provided by GetDataBack to fix the MFT with a free program. I only have one folder that I actually want to recover, so it feels silly to pay $70. Or if folks have other suggestions of how to try to recover it for free, I'd love to hear. I made an image of the drive just in case it's mechanically failing, but I think it was some sort of shutoff sequence that corrupted the partitions.