I went to go look at stuff today and find the thermostat housing, and I noticed their was some green fluid (presumably radiator fluid) in directly under the thermostat housing. Guessing well at least hoping their is a gasket leak on the thermostat housing. I am going to flush the system sometime this week. What else could possibly be the issue here or where could that be coming from.

Am I going to run into major issues here with that fluid being there?

 

Dude mine pools coolant there once and a while too, been doing that for as long as I have owned it.
The problem with mine is there is a nick in the goose neck so the radiator hose does not seal correctly and under the right circumstance it leaks, not much, just enough to leave a small puddle on the valley pan.
I used to wash it away with water every once and awhile, now I just dont worry about it, it wont hurt anything and will evaporate over time.
I dont loose enough coolant to worry about it, I add maybe half a gallon a year, maybe.