Number porting issue from Verizon to Vonage

I am wondering if it is possible for a partial port from Verizon to Vonage only partially work? A business in Philadelphia ports some of their many DID numbers (20) from their Verizon PRI to new Vonage phones (same business location). When a test call is initiated from a cell phone to the Vonage phone, these ported DID numbers will ring the Vonage phones every time. However, if you initiate the same 10 digit call from the legacy phones (placed next to the Vonage phone) within the business, the call will go out of the local Verizon PRI, and then Verizon routes the call back into the same business on one of their other PRI’s (I captured a D channel trace to prove this).

Therefore, since “the initiating service provider switch (Verizon) launches a query to its LNP call routing database to determine whether the telephone number has been ported”, IS IT POSSIBLE THAT Verizon’s LNP call routing database is not updated locally, but is at a more global level? This would explain why calls initiated from within the local business using the legacy phones don’t ring through to the Vonage phones.. I’m guessing. Please help