Official answer is the phone will not be in Verizon's database and you will likely not get a new activation to work. However, if you activate another phone on Verizon with a nano SIM on the new line and then put that SIM in the T mobile iPhone 6, it will work. It does not work with phones prior to iPhone 6. The phone may show up on My Verizon as "not a Verizon device" but it works normally. Good luck.
If you look at Apple specs for the T-Mobile version of the phone, the GSM version of 1522, it doesn't have CDMA for Verizon.
TRy the phone. But if it doesn't work, you know why.