Alright, instead of adding another fan, I decided to model and 3d print an air duct. Here's the file should anyone want to try. The attached model is a revision of the one in the photos. This takes the shunt resistor (I think) into account. Print using a 0.4mm nozzle at 0.2mm layer height. I recommend PETG since that heatsink will get hot enough to melt PLA.
It's currently idling at 43c so that's a win in my book. The fan is a little quieter now as well.
Doing $diety_of_choice's work right there.