This is really awful; you put so much into it and to have it not look like that when you arrived .... there are no words to describe the feeling! I can see why you were so upset, I would be too.
What time did you set up the cake and what time did guests arrive at the reception? I think this is part of the problem - the cake was set up so you could get to the ceremony and in the meantime, they realize the room set up is incorrect or wrong in some way. The pastry chef isn’t thinking about the room set up, just that you have a cake table and you’re all set.
When the function manager realizes they need more tables or something isn’t quite right with the room set up; that’s when they realized they needed to get into the closet behind where your cake was set up. And very probably the cake table isn’t on wheels and they can’t just slide it over. So they pick up the table and begin to move it, and that’s when things start to shift. They probably shifted enough so that your beautifully decorated cake didn’t look so beautiful anymore and now they’re really panicked about it and they do the best they can, which is not equal to what you did. I don’t think there’s a villan who thought your original set up was not beautiful, because it was; I think they tried to make the best of a bad situation and didn’t have many options.
Most venues tell me I can only deliver an hour before guest arrival; if I were to arrive before the designated time, they would refuse delivery. The venue has a sheet that goes to the various vendors (florist, DJ, baker, etc) and this sheet tells what to expect in terms of what the delivery parameters are; some hotels send it to me directly, others give the sheets to the bride to distribute to her vendors.
I know it sounds like I’m being harsh and I don’t mean to. But there’s a good reason for setting up the cake as close as possible to guest arrival - you don’t have to worry about something completely unrelated to your cake disturbing all the hard work that goes into it!
Your original picture is beautiful and hopefully, you can get that one into their album