Replacing Failed HDD on F5 Big IP 8900

Attempting to replace a failed HDD on a 8900 series big IP using https://support.f5.com/kb/en-us/solutions/public/12000/700/sol12756.htmlRAID.

Currently there is a single array (MD1) with a single member showing ok. When viewing the other disk it shows as undefined. Per F5 after attempting to add the disk to the array you will see replicating and then undefined which could take from 30 to 60 minutes. However, minutes after the attempt the daemon.log shows events below and after several hours the drive is never added to the array successfully.

info: Disk Self-test-- beginning test error: Disk Self-test-- test of sdc failed; 4

Has anyone had this experience?