Human maths are a product of human observation and symbolic interpretation. But, IMO, that is looking at it backwards. Human maths are not invented, the symbolic language we use is invented, but the values and functions on which our mathematics are based on are present at time of observation, else they could not be quantified and symbolized to begin with.
Newton invented his theories from recognizing the "regularities" exhibited by various natural phenomena and that these regularities can be assigned "values", precisely because they were regular and could be quantified and qualified with symbolic language. He did not need to know that the speed of light was a constant.
But even your citation of SOL being a universal constant is a recognition of a mathematical values which applies to the speed of light. The relative value we use to quantify that value is arbitrarily selected for human convenience.
When cosmologists tell me that they are only "discovering" the existing universal mathematics of what they are observing, who am I to argue? If a cosmologist tells me that gravity is a result of an inherent mathematical ordering equation, which is pervasive throughout the universe and demonstrably a quality of space-time fabric itself, who am I to call him/her wrong?
We did not invent Universal mathematics, we translated them from direct observation or by testing.
Our conjuring of the Higgs boson was a result of a mathematical predictions, not of throwing a bunch of stuff in the LHC and hoping for the best.....