Concur with OP. My wife's Galaxy S4 is "under network coverage" as determined by the little symbol at the top of her screen, plus dialing #48 gets the "you are under network extender coverage" voice.
When I try to dial #48 with my Ip6, using the same number that I had on my G2 with Network extender coverage, I get a Verizon voice saying that the call cannot be completed.
We need to get this fixed.
Update: Got it working. I went into Verizon, My Verizon and clicked the plus sign next to the search box and then selected manage network extender from the list of choices. I then went in and changed from all users to the 3 people who use my network.
I then pulled out the power for the network extender and plugged it back in. When all the lights were on, I moved within 15 feet and dialed #48 and it told me that I was under network extender coverage.