If something is non-measureable, it's either:
>not-yet-measured
Something which is complely possible to measure, but we either dont have the means, or simply haven't bothered to measure it. Irrelevant to the question in hand.
>relatively unmeasurable
Something which is apparently unmeasureable due to the limitation of human perception, but can be indirectly measured due to it's relation with other, measurable, objects. A simple example of this in the field of physics would be radiation.
>absolutely unmeasurable
Something which is completely impossible to be comprehended by the human perception. Now, here we fall into the dillema you proposed: Are absolutely unmeasurable formally unmeasurable (ontologically, by essence) or materially unmeasurable(impossible to be measured simply by the limitation of human perception)? Well, due to the inherent nature of the object of this question, it's impossible to determine weather it's material or formal, thus making this discussion irrelevant.