I agree with LP members you should have reported to the Police. The police take cases theft of money very seriously. You should have used the Dubai E-Complaint system which you could have logs your complaint.
I will enclose you the Dubai E-Complaint system web- site in case you change your mind – You need resister your name make a password log a complaint) the web site has option for Dubai Police.
You should have also log a complaint with Hi Hostel via Email.
Dubai E-Complaint web site)
http://www.ecomplain.ae/Main.aspx?Lang=EN
Good Luck
