There is big potential for a price war. Qantas never gives up market share easily. You are probably right that it may be United to struggle but VBA will have to be careful.
Don't forget they have to fund the 2nd and 3rd 777 at $400 Aud a pop. There goes the cash in the bank and a possible capital raising for VBA.
I would think this is the reason for the subdued share price.