Last I heard, the television integration was broken, but I don’t have one so I don’t know if it’s been fixed yet. Probably the best thing is to check with support.
Here’s the community discussion thread on the problem, you can also check there. (This is a clickable link)
As far as Alexa integration, it is supposed to work with the Samsung connect using the exact same Alexa skill as the original hub. I haven’t heard about any problems with that. However, I believe you do have to be using the SmartThings mobile app, not the Samsung connect app, so maybe that’s what you meant.
Also, there is a known issue where smartThings only exposes one “location” to third-party services, including Alexa and IFTTT, and you don’t get to pick which one. 
They say they’re working on fixing this, but no timeline.
https://support.smartthings.com/hc/en-us/articles/207808076#Locations
Since Samsung connect often gets added as a separate location, then that could also be the problem.