Unless the phone gains support for LTE band 13, I seriously doubt this phone will be a good option for someone on Verizon.
I could be wrong, but at least in my area (Washington DC area) they are rolling out B66 on towers on T-Mobile.
-99 dBm for LTE isn't that bad of a signal. My Pixel 3 XL is getting a LTE signal of around -109 dBm. Anything -115 dBm and up on the other hand is a different story....