You can't sell till you have probate. I assume the 3 of you (or 1 or 2 of you) are the executors. I am not a lawyer but would think that if the house is sold by the executors (in other words, it is never transferred into your own names) then any shortfall would have to be dealt with by the executors. It would have to be met out of any other assets in the estate, but if there were none then it would be the same as any other debt of the deceased which can't be paid from the estate - i.e. the creditor would have to write it off. It follows from this that your personal credit ratings could not be affected.
However, a big word of caution. If your solicitor says it is a grey area then my ideas may well be quite wrong.