I do sympathise, as I imagine it must be hard - I hope you have a solid alternative that you are able to embrace. I suspect the reasons the school are unwilling to be drawn are two-fold: a) they may not want to admit how many people have effectively turned them down (freeing up waiting list places) and b) actually, what happened in the past is irrelevant as, just because it got to "n" on the waiting list last year, or "o" the year before does not have a bearing on where it will get this year. I suspect they do not want to give you false hope or make you feel you have no chance when there could be one.
Can you focus on the alternative and then, if an offer comes from this school embrace that as an unexpected bonus?
If only human behaviour were so simple.
Thanks for the suggestions.