It looks like bassguitarman was recently added to Tomatocage's trust list which is what caused you to have negative trust by default.
The fact that an account was sold is not a reason to remove negative trust. You will need to try to work out the negative trust with bassguitarman and if necessary contact TC, however TC is unlikely to remove him if the rating is accurate.
How can you tell who added an account to the trust list.. Like how do you know it was TC who added bassguitarman?
The above link will show you your entire trust network by hierarchy, you find the person who is in your trust list then scroll up until you see whose name is slightly less indented