It could be as simple as your quotes. You're using double quotes inside double quotes without escaping them. Two options:
M.
CAMLQuery: "<Query><Where><Eq><FieldRef Name=\"Status\" /><Value Type=\"Choice\">Closed</Value></Eq></Where></Query>",
or CAMLQuery: "<Query><Where><Eq><FieldRef Name='Status' /><Value Type='Choice'>Closed</Value></Eq></Where></Query>",
M.