Script Assertion each statement

This is just a guess from looking at you post above, where you define your expected results (I've reformatted for clarity):

def expectedResults = [
                       [
                        criteriaName: "Impact_On_Functioning", 
                        levelOfCareName: "Hospital_Level_of_Care", 
                        outcome: "Met", 
                        parentCriteria: "null", 
                        parentCriteriaName: "null", 
                        programName: "Hospital_Level_of_Care"
                       ]
                      ]

I see that you are representing your null values as the string "null" which is different to a true null value. But when logged out would look the same. Try changing your expected reply to:

def expectedResults = [
                       [
                        criteriaName: "Impact_On_Functioning", 
                        levelOfCareName: "Hospital_Level_of_Care", 
                        outcome: "Met", 
                        parentCriteria: null, 
                        parentCriteriaName: null, 
                        programName: "Hospital_Level_of_Care"
                       ]
                      ]

Note: How I've dropped the quotes around the two null values.

As I mentioned this is just a guess but could be worth a try.