So I figured out my solution, see below if you’ve come to this post looking for an answer.
I Un-ticked “Auto Activate” on “Spawn System at Location”, set my desired parameter (I changed its name since my first posted screenshots from Lifecycle to LoopDuration, in case that confused you) and then set the Niagara system to “Active”, thus overcoming my issue of needing the system spawned to get a reference to that system so that I could alter it’s user parameters.