Diesel Bombers - Truck Not Starting :(

hey everyone I was wondering if there are any diesel people out there? My truck isn't starting. here is some info -->

My truck is a 2006 2500 5.9L and hasn't started in about 2 weeks. batteries are fully charged.

Here is what I have replaced -->

Fuel Pump
Fuel Filter
Pressure Relief Valve
Heating Grid
Intake Heating Relay
Injectors and Tubes
Injector Pump
MAP Sensor

I'm wondering if there is a relay or sensor I'm missing.

I'm at a loss of what can be left. It seems like there isn't enough pressure.

I'm hoping someone here can help me figure out what else is left to check.

Thanks in advance,

Zach

Here is the video of me using a bit of starter fluid ----->

Here is the video i took yesterday after replacing the crush washers on the fuel lines --->