Hi Larry,
Just a few ideas for you in the event you want to spend anymore time on this before it goes back to the dealer.
Since you were able to pass an RF modulated signal (assuming channel 3) but not a satellite signal, it is my sense that there are one or more bad fittings (connectors) in the line or maybe a splitter with a passband lower than the satellite signals. If you have the time and are so inclined, before taking it to the dealer, you may want to check all of the F-connector fittings in the lines. Look for two main things:
1. That the center conductor is not too short - it should be flush with the end of the connector and
2. That there are no aluminum braid (shielding) hairs or foil wrap (more shielding) wrapped around or near the center conductor as you look down into the end of the connector. If there is, use a tiny screwdriver to move these items to the outer edge of the connector.
If the center conductor is too short, you will need to cut off the old connector, strip the cable end and crimp a new connector on.
If for some reason, there is an RF splitter in the satellite antenna lines from the factory, this would be in error and it would need to be removed (use an F81 barrel splice) as they will not pass the higher satellite frequencies from your LNB.
Jim