iona costello , 51 , and daughter emily went missing on march 30 .
recognized by someone at the new york hotel they were staying in on sunday .
nypd officers questioned them and say the case is now closed .
iona called her mother , diana malcolmson , at 3:30 a.m. on monday morning to tell her she was ok .
` she had n't listened to the news . she did n't know she was causing all this trouble , ' said malcolmson said .