This is precisely why, in spite of there being some oversimplifications that do likely exaggerate the final numbers' magnitudes, that Enderlin is still solidly EF5. You could have some factor not being taken into account that would reduce the windspeed by 10% (which is a very significant disparity) - but 10% of ~230+ mph does not take it below the threshold. You can run thousands of Monte Carlo simulations on the thrown object in Enderlin's case, and I would be mindblown if the number of runs yielding sub-EF5 intensity fell within three standard deviations (or sigma values). In fact, I wouldn't be surprised in the slightest if literally zero model runs displayed sub-EF5 level winds moving that object in that manner.
Enid, on the other hand, displayed not only a much lower median windspeed value, but given the range of values on the median, absolutely had multiple runs that yielded sub-EF5 intensity in its modeling and calculations, and likely more than enough runs to exceed a threshold defined by the sigma values. If this is the reason why they held back granting Enid an EF5 rating, this is entirely reasonable, from both a physical and statistical standpoint.
Big reminder though, I am discussing things that I am completely assuming based on my knowledge as to how decisions are made in academia. If this really isn't the reason why they kept Enid from receiving the EF5 rating, then I'm quite frankly a little dumbfounded on the decision to maintain EF4 for it, given the supporting data and evidence.