In which case, using so many tokens on that one player seems a bit silly. You would have been better going onto the scout market and bringing in 2 or 3 scout players for less tokens, who would have also cost you less in money.
Pretty sure that is correct. The selling person will see their account fall into a negative balance - forcing them to correct the balance or lose players after 7 days. Its a nasty trick to pull on someone as it will all but screw up their account (unless they have thousands of tokens to pay for bank loans).
There were rumours that Nordeus would correct the losses if the user reported what had happened, but having seen their (lack of) action on other issues I wouldn't be holding my breath on that being the case.