How much you want to bet the "investor" took no loss on this business venture and was paid back his investment before customers were paid back their money. If there was really an investor and they weren't stupid they probably had a contract written up and it said something like, "If Tom is an idiot and can't get this done I have recourse to get my money back from his hide." Maybe he even put his house up.
Any smart investor is going to invest in a manner which makes them a preferential creditor in the even of everything going to hell, regardless of whether they've traded funds for equity or made a loan to the business. Only complete idiots invest in a business on a "pay me back whenever, however" basis. Wise investors know their exit strategy and write all sorts of things into the contracts to protect their interests.