My apologies for not being helpful, Buddy.
However, if you read that thread I referenced, it doesn't appear that you can use the Verizon Network Extender.
Here's Straight Talk's response:
"We would like to take this opportunity to apologize for any inconvenience you may have experienced with the delayed response about your inquiry. We currently do not support network repeaters or network extender with our Straight Talk phones. Thank you for your inquiry."
Here's a real life experience from a person trying to use the extender:
"I had Verizon, with the network extender at my home. I switched to Straight Talk. The network Extender continued to work with my Straight Talk CDMA phone, UNTIL my wife cancelled her Verizon contract. As soon as there were no more Verizon users in the household, the extender stopped working. So it appears, as long as someone in the house has a Verizon account, the network extender will work. It worked with my straight Talk CDMA Samsung Galaxy until my wife cancelled her Verizon account."
So that's why it appears to me that you have to have an actual Verizon account for the Verizon Network Extender to work. Being a Straight Talk subscriber, you will NOT have a Verizon account. You will have a Straight Talk account with a phone that uses the Verizon network. It's not the same thing.
No, from the way I understand it, you have to have the Verizon Network Extender registered with an actual Verizon account. Using a Verizon MVNO such as Straight Talk, you will not actually have a Verizon account.
Straight Talk will not support it at all.
Here's a thread on Howard Forums about it (copy-and-paste):