A:Answer Hi Eli,
No, you aren't missing anything. Hole C should be located in the middle of the wall plate. I have shared the installation guide of this model below. Please visit the link and turn to page 10 to align the wall plate and its instructions.
https://downloadcenter.samsung.com/content/EM/202109/20210903120631727/SMH8165_XAA_DE68_03587A_10_EN.pdf
Should you have additional questions, please feel free to get back to us via the following options:
1. Facebook Messenger: http://m.me/samsungsupport
2. Twitter: https://twitter.com/messages/compose?recipient_id=18768513
3. Samsung Community: https://us.community.samsung.com/t5/Samsung-Community/ct-p/us
4. Phone Customer Care: 1-800-726-7864 (1-800-SAMSUNG)
When you message us, please provide us with this reference number 1148131338 to help our team pull up your information.
Leo