Still No Cabin Heat while driving? 08 E90 328i

There is a thermostat in the Oil Filter Housing Unit apparently?. Nobody really knows about it because most people dont own a BMW beyond 200k miles lol. I am chasing a issue where I have little to no cabin heat when I drive. I've replaced literally everything except that OFHU thermostat.

If that doesn't work, I'm gonna assume my brand new thermostat (next to waterpump) is bad out of the box. The old ones weren't even bad at 240k+ miles.

Can't be a clogged heater core, right? I have strong coolant flow when I run bleeding procedure, so if clogged, then I'd barely have a stream, right?