Currently the IHC app Alexa skill only sees TVs.
The trick to learning a DVD player or something else is set it up as a TV.
1: select add device from the app
2: select TV and from the list select a brand that isn't yours.
3: go through the setup checking no when asked if the power button worked
4: once the app has gone threw codes a info screen will appear select custom learn.
5: a templet will display allowing you to learn each button.
6: once done rename the device and choose a different Icon
7: ask Alexa to discover devices
I've setup my Sat Dish receiver & DVD player this way and Alexa sees them.