The Stay theme adds Rooms and Testimonials to the dashboard by default. If Testimonials are not enabled, any Testimonials added will not show up. If Testimonials are enabled, another Testimonials tab will show up in the dashboard.
Thanks for the report.
Also: this could be changing soon due to experimental CPT behavior that's in development: see https://github.com/Automattic/wp-calypso/labels/Custom%20Post%20Types%20%28CPT%29.
Yep, this must be due to Calypso's CPT handling. Changing issue labels accordingly.
I'm going to close this as working-as-intended, specifically because these are technically two separate post types, hotels_testimonials
(as registered by the Stay theme) and jetpack-testimonials
(as enabled under Settings > Writing).
FWIW, the wp-admin navigation is also affected by this oddity:
If encountered, we can suggest that the users disable testimonials from Settings > Writing and leverage the theme-registered post type, which may be better displayed on the front-end.