Before I repost my answer to another kinda same thread, how are you able to turn off your TV via Alexa? If it's by using harmony, nvm. But if not, do share. I'm curious.
Now, I also have Samsung Smart 4k tv. So here is an idea for you if you have same remote like mine which has a built in mic. In case you're not aware of your Samsung remote voice capability.
I think he wants to control his Samsung with echo. I don't think you can do it that easy. You need a harmony remote for that. But I just console myself that my Samsung remote can voice command my TV too, just not hands free. I've to push a button to use the mic in remote. Are you sure your remote does not have voice command like mine?
I'm basically saving you grief in setup and cost of harmony remote. I am telling you, you don't need echo to voice command your TV if your remote has built in mic in it, like I have.