Disk check failed, you have cyclic redundancy check errors, the WD utility check failed, you have a 400 day estimate for scanning the disk. This all points to complete disk failure with many irrecoverable errors which explains the 400 day estimate - it is failing to access the drive at sector level and is making repeated tries on each and every sector on the drive. If, as you remarked in your first post, time is not something you have plenty of then I would not spend any more of it on this drive - I am convinced it is beyond all hope.