It seems a crazy thing to do,some have, and discussed on the forum, search for the post.
Your question was even asked and answered in this thread.
Why do you need to destroy it ?
I suggest if you are going to do it ,use all the resources first,like all other buildings once you destroy it ,all the benefits are gone, and everything used to build it , isn't given back to you.
Many have asked that Plarium remove all unused towns and strongholds, but am aware if they have done either of these in any kingdom.
Apart from that, the only player that can demolish the stronghold is the chief, so if you were the chief and passed it to someone else,and they removed it whilst you were not playing,then you didnt really have a say in what happened.
Giving the chiefdom to someone else even on a temporary basis, can be a risky thing to do as you have no control of what happens in the interim, and if someone did demolish it in your absence , I think its probably unlikely you will get it back.
You could directly ask the help team, but I suspect its going to be too late to rectify matters, especially if the space is no longer available.