your export file has a bunch of errors
a) the same meta keys are 2x in the xml for the same item but with different values
b) there is a bunch of metadata missing
this has nothing to do with me and i cannot help you there
(i suspect) you have been using the wordpress import/export and you somehow ended up with this messed up xml.
maybe you did something else somewhere else that caused that (perhaps multiple merged exports or something). i do not know.
fact is, that wppizza menu items are just regular custom post types with meta keys stored in the db as wordpress does it. exporting these items is nothing i have any influence over