Knowledge vs. Not

Groupie

Knowledge vs. Not

We have a local rep in a local branch that has been working me a solid for most of this year. I walk in with any unlocked Sprint phone, and I'm walking out in minutes, very satisfied.
I have a LG G6, my daughter, using a Moto Z2 Force Edition, son is on a LG V20 Mom has a Stylo 4, fiance is using a Stylo 3, and all were Sprint devices.
Today, someone new was working in this branch, and low and behold, he can't get either phone on my favorite network. One is a Sprint LG G7, the other is a V20.
This guy calls Boost for compatibility, with a 'no' answer.
Explaining that I've met a guy with a G7 on Boost, and that my son is using a V20 now on Boost and has been doing so for 5 months.

If it's doable, why can't everyone?