Ok, so just want to post this for other members can use.
Samsung Smart TV Remote CAN be made to work with Verizon FiOS STB.
Here are the steps (and one trick that I only accidentally found):
1. Make sure your Smart Remote is paired with the TV (I got a new remote that had to be paired first). It has to be a genuine Samsung remote that, when holding the Back and Play buttons, shows on TV and pairing is successful !
2. Make sure STB is connected and fully functional
3. On Samsung TV go to Source --> Universal Remote
4. Select New Device --> Cable or Sat Box --> TV
5. When asked to select your provider DO NOT select Verizon FiOS Digital (as it shows on my list. This one won't work !). Scroll down and select "My service provider is not listed"
6. Then from this new list select Verizon.
7. When prompted to change channels, they do change. Press Yes to ack everything works and you are all set.
My STB is HD QIP 7100 1
Was struggling for hours with this, selecting Verizon FiOS Digital and channels would never change. The trick is to select Verizon, only on the second screen.