Well, here's a Latinist returned, just in time it looks like.

Marianna, 'status quo' was originally the nominative case -- the one used when the expression is the subject of the sentence, and in English also as an object. So you have, "The status quo is not satisfactory," or "He considered the status quo not to be satisfactory" [objective/accusative case]. However, in proper English, we have preserved the Latin dative/ablative form 'statu' when the word 'in' is used, as, "It was decided to leave the matter in statu quo."

Pronuncation is short 'a' for both forms, and the 'u' is also short, so it's 'stattuss' or 'stattoo'.