First Aid Test in Disk Utility returned this:
Running First Aid on “Seagate Backup Plus Drive” (disk3)
Verifying storage system
Performing fsck_cs -n -x --lv --uuid 4AF87A87-C7FD-4602-9219-2AB85A1841EB
Checking volume
disk2s2: Scan for Volume Headers
disk2s2: Scan for Disk Labels
Logical Volume Group 4AF87A87-C7FD-4602-9219-2AB85A1841EB on 1 device
disk2s2: Scan for Metadata Volume
Logical Volume Group has a 24 MB Metadata Volume with double redundancy
Start scanning metadata for a valid checkpoint
Load and verify Segment Headers
Load and verify Checkpoint Payload
Load and verify Transaction Segment
Incorporate 0 newer non-checkpoint transactions
Load and verify Virtual Address Table
Load and verify Segment Usage Table
Load and verify Metadata Superblock
Load and verify Logical Volumes B-Trees
Logical Volume Group contains 1 Logical Volume
Load and verify FCAA5230-823C-4739-97D0-A74A7EEF6990
Load and verify A0CE9EC2-E381-44A0-9B88-CC37C76C8B41
Load and verify Freespace Summary
Load and verify Block Accounting
Load and verify Live Virtual Addresses
Newest transaction commit checkpoint is valid
Load and verify Segment Cleaning
The volume 4AF87A87-C7FD-4602-9219-2AB85A1841EB appears to be OK
Storage system check exit code is 0.
Repairing file system.
Volume is already unmounted.
Performing fsck_hfs -fy -x /dev/rdisk3
File system check exit code is 8.
Restoring the original state found as unmounted.
File system verify or repair failed. : (-69845)
Operation failed…
I did some digging and found this video, which didn't work for me. But I read through the comments and people commented on one thread saying "force quitting "fsck_ext."" worked and it did! The external drive is corrupt but I was able to mount it and transfer all of the files to a new drive.
If anyone has this issue, try this video and if that doesn't work read through the comments:
Force an External Mac Drive to Mount via Command Line Terminal Commands in Mac OS X:
https://www.youtube.com/watch?v=QMvYHgQOEvA