Verizon cellular blocking RTMP ingest?

Anybody ever heard of Verizon cellular throttling or blocking RTMP ingest?

After experimenting with our remote live stream setup, I am suspicious that this might be the case, and I’m wondering if anybody has any workarounds, or suggestions of something I may have missed. Here’s the story:

We recently began trying out a remote streaming setup that uses the Gl.Inet AR750s tethering to a ZTE MF833V modem with a Verizon Data only sim card.

We really only need low bit-rate streaming for our remote events, and with the ZTE clocking in at approximately 5 to 6 mb/s upload speeds when connected to a Macbook Pro, we thought we were in the clear.

Here’s our setup: ZTE Modem with Verizon data only SIM → via usb tethering → GL.Inet ar750s → via LAN ethernet → ATEM Mini pro → via RTMP → Youtube Live

Here’s the issue: When the ZTE modem is connected to the AR750s, per the readings under “Clients” on the Gl.Inet control panel, the ATEM only gets somewhere between 100 to 200 kb/s upload speed when connected to the Gl.Inet’s LAN ethernet port (not nearly enough speed to send a stable RTMP feed to Youtube)

With a Macbook Pro connected to the same Router and modem combo via LAN ethernet, upload speed tests again yielded 5 to 8 mb/s upload speeds.

I’m quite certain the problem is not with the router, as I understand that a lot of people use the AR750s with the ATEM mini pro, and my company has used it’s mobile tethering feature as a backup in the past.

This led me to believe that there might be some sort of interfacing problem between the ATEM and the Verizon cellular internet connection provided by the SIM card in the ZTE modem. With data speed checks on other devices all turning out regular speeds, the ATEM (which is sending RTMP to youtube) gets comically low upload speeds. My suspicion is that Verizon somehow blocks RTMP ingest over cellular internet, or maybe some other restriction is keeping the ATEM from using the cellular network at top speeds.

I am honestly quite puzzled by this issue, maybe I am missing something?

Anybody have any suggestions?