You definitely can get a near perfect finish in buttercream and ganache, I use both as I hate using fondant.
It looks to me like she ran out of icing and the didn't want to try to colour match the icing by making another batch.
It also looks like she ran out of time.
The amount of flowers you originally wanted plus the cake would have been cheap at $140.00.
I don't make cakes professionally but I do make them, the last one made for my Grandma and it cost me about $60+ including cake board and ingredients (8 inch cake, iced in a mirror glaze, over a white choc ganache, filled with swiss meringue buttercream, cake was a vanilla cake so admittedly expensive fillings and icings but you haven't said what yours is?).
The amount of time to make the basic flowers and roll the pearls plus time to make the different icings, filling, cake etc amounts to hours. Yours had a lot of hours just in the flowers if it was meant to match the oiginal.
That being said, if she gave you that price and said she would make the original photo cake then what she charges for her time and to cover her costs is her decision so if she wasn't going to end up making much/anything from your cake then that was on her and yes I would be disappointed to receive what you did.