Bill query

About 3 weeks ago 29th May 2015,i hosted My Graduation Party at Southern Sun Hotel in Sandton. When it was time to pay I swiped the bill not knowing some people had paid cash and some swiped. When I did do a follow up on the Bill, I received a receipt from the manager which im pretty convinced that it was edited, the amount was completely different from the one from Sat, The amounts did not add up to the total amount, the Vat number was missing from the receipt and top of that we swiped at diff times but that bill showed same time. This also included a tip I did not give to the waiter which was R364,00 how that was calculated i'm still puzzled. The waiter then told my friend that I did not settle my bill before I left, she then gave him 350 cash which is what he demanded. When I asked about this, he denied it, and iv requested to see the cameras, since the money was given to him by the bar area, but the manager does not respond to my emails nor return my calls, its been 3 weeks now .I recently graduated and i'm very fussy when it comes to money, i work for it and I will not stop until I get the answers I need. Please help me understand.