Unfortunately it doesn't work like that. Firstly you dont need to keep the 800k in the bank and secondly the GDP has very little to do with banks "cash flow and liquidity"
Seems like you need to get some basic financial lessons yourself!
You'll be in no mans land. If you get refused entry then Thai Immigration may impound your bike or send you back to Cambodia with your bike. The bike won't be a reason for Immigration to let you in the Country.