I am all for Nick to get his answer, as to how many offspring were produced, and see no harm in his asking nor in his receiving an answer.
With that said,
Although numbers/percentages can be used, to determine a higher likelihood that a certain gene does not exist, there comes a point when it may not matter how many offspring were produced.
Well, unless it is something so low as having produced, for example, only "one, two, or three" total offspring (which would not indicate the existence of, or non-existence of, a certain gene).
This is because time needs to be a factor. Such as, how many years/seasons is it reasonable, vs. Unreasonable, to keep "test breeding".
Also,
not necessarily in this case but, in general, what if there is a case where it comes to having to take legal action. There is a statute of limitations, for this type of civil matter, that needs to be considered (dependent upon certain actions or lack of certain actions).
Although, ethically speaking, there would be no statute of limitations.
....