My neighbor's tree.......?
Answers:
I don't think this is a matter of over watering, think about it. Trees are meant to be outside. If the tree has been there for years it has had all levels of water. From having to use a sprinkler in dry times to being delouged by rainfall. If the maid put straight poop on the tree and it was (sorry a little graphic) fresh, it was probably too "hot". Too heavy in chemicals and acids. This is going to be a problem. Tell your neighbor right away. You don't want to be held responsible for killing the tree.
Other answers:
yes e-mail her
yes e-mail her
You may have overwatered the tree. Overwatering kills more plants than diseases.
Yes email your neighbor. And yes, involve the maid. Tell her everything. No need to cover up for anything or ANYBODY.
You should e-mail your neighbor and tell her what happened. Ask her if this is a normal way for the tree to react to geep. If not, ask her what she wants you to do about the tree. This way you are informing her before her return of what to expect; also shows you are acting in a responsible way concerning her property.
Shovel the stuff away from the tree, it is two high in nitrogen and it will kill the tree. the more you water it the more nitrogen you will put into the soil.
Call a professional nursery for professional advice.
You were asked to keep an eye on things and are not expected to be a tree surgeon. Just report the problem/situation to your neighbor and let them decide what to do. You will have fulfilled your obligation.