I see that you removed the URL from your question. As I remember, it was quite long and complex, so it's unlikely anyone would have remembered it. If someone was going to mess your tree up as a prank they probably would have done so already. You're probably safe now.
However, as I said before you should copy your tree over to a new account for security purposes. DON'T post this one's URL on this forum. I'd also recommend again drawing this directly to the attention of Family Echo, as it could be a serious security problem.
I hope this helps with your problem, and I'm sorry that my last answer 'totally misses' your question.