Google-calendar – Cannot add Calendar Resource to My Calendars

I have a G Suite Meeting Room and I want to manage its calendar. I'm following the instructions on this page to add a Calendar Resource to "My Calendars", however the section My Calendars (capital C) and referenced "+" button in Step 2 below is not present.

Note: This question is specifically to add the calendar to "My calendars" so it can be managed, not to "Other calendars" where it cannot be managed or edited.

What am I missing to complete these instructions?

Here's the instructions:

• https://support.google.com/a/answer/60766

I have the following pre-requisites:

• "administrator account with Calendar and Super Admin privileges"
• "a calendar resource (such as a meeting room) for your organization" – resource with "Calendar-based room release" set to "On" and "Type" set to "Conference Room"

Here's the screenshot from my user with the required "administrator account with Calendar and Super Admin privileges". There's no My Calendars (capital C) or "+" as specified in Step 2 above, but My calendars (lowercase C) does exist without a "+".

Here are the steps: