In Galaxy S7, cannot disable Samsung Reactivation Lock Summary

I'm trying to install a custom build of LineageOS following the instructions here. I was attempting to load a recovery image using heimdall when I'm told 'Recovery Check failed'. It turns out Samsung has something called Reactivation Lock, but the settings to disable it aren't present on my phone. I actually called them and they said it had been replaced by Google's Android Device Manager, but there's clearly something preventing me from loading a recovery image.

I can't link to it because of reputation limits, but the recovery image I was using I built from source; it's linked on the home page of LineageOS. I did also try it with the images built by Team Win Recovery Project with no luck.

I appreciate any help you can give me.

Steps

I rebooted into 'download mode' using $ adb reboot-bootloader. Heimdall recognizes the device: 

$ heimdall detect

Device detected

but when I try to load the recovery image I get an error:

$ heimdall flash --no-reboot --RECOVERY out/dist/recovery.img

Uploading RECOVERY
100%
RECOVERY upload successful
Ending session...
ERROR: Failed to receive session end confirmation!
Releasing device interface...

and on my android it shows SECURE CHECK FAIL : recovery in the top-left corner (in red, if that matters). Rebooting into recovery mode just reboots the phone normally.

Specs

Model: heroltevzw
Model number: SM-G930V
Android version: 7.0
Patch level: August 1, 2017
Sounds like your bootloader is locked. Going from your model number I'm guessing you have the snapdragon variant with Verizon. If that is true just flash stock firmware through Odin. Stock meaning the last version your phone was running on before this happened. I'm not familiar with anyway to unlock the boot loader. Also I personally use Odin when I flash my s7.