@tigerpro
Do you think this could be an issue with the 910T3 model of the Note 4? Cause I'm having the same issue as OP, and download mode says "Product Name: SM-N910T3", and from what I've heard, the model 3 is slightly different (and likely a bit rarer)

Okay to keep it brief, today I tried installing Ubuntu Touch on my Galaxy Note 4.
After the install (After the "Updating" screen) the phone gets stuck on the Samsung Galaxy Note 4 screen with "KERNEL IS NOT SEANDROID ENFORCING" in red at the top (and "Set Warranty Bit : kernel" in yellow bellow it)

I have tried reinstalling it at least 5 times now (I'd install TWRP, then an Unofficial ROM, then do all prerequisite, though this last time I found I was able to just do it from TWRP), and the installer has been running on Linux ChaletOS

According to download mode (Where it says "Product ID") I have the 910T3 version of the Note 4

@m4l490n
Have you found a solution? I'm having the same issue myself