See, this is why I said "we would need to talk about the concept of 'senses'" earlier. Or you could make it about "detectable" instead.
We could reduce it to "our senses"... human sight, smell, taste, touch... that would still leave a lot of other "senses" that could detect stuff. We could reduce it to the senses of "living" or "conscious" beings... that would still leave a lot of other things that could be used to detect stuff.
If something is really "undetectable"... and it seems that you, dysert, hold to this definition, there is really literally
no way
to detect it. That means it doesn't have any influence on the rest of "reality"... or else you could detect it by this influence.
And if something hasn't any influence on reality other than itself... why bother with it? It is indistinguishable from "non-existent".
Considering that you said that the acceptence of something undetectable would result in the appearence of "miracles" and the knowledge of "the Creator God", it seems you didn't come to that conclusion. I would like to know why.
And I would also be interested to find out why you excluded the pink unicorns.

Seriously, I do.