Bootcamp not detected in option boot menu

MacOS 10.11.6 (El Capitan)
iMac 27-inch late 2013
Using internal drive from factory

Installed NTFS for Mac to write to external disks. Afterwards, cannot boot into Bootcamp and Bootcamp volume not seen in the option boot menu. However, Bootcamp DOES appear in Startup Disk control panel, which is different than all the articles I've found found in the knowledge base.

When system tries to boot into Bootcamp, I get the basic DOS-looking error regarding not seeing a valid device to boot from and asking me to insert a boot disk and hit any key.


Thank you,
Nathan