I guess you are talking about room temperature.But I have stored tomato seeds at below zero temperatures for over a month in a sealed mason jar.It didn't hurt the germination at all.Such extreme cold temperatures don't kill the pathogens either I don't think.
So here is what I'm thinking as a way to kill the pathogens.
Start a fermentation with just a tomato and the juice.
Remove all the seeds from this tomato, doesn't matter what kind of tomato.
Get a nice fungal coat going and then add the suspect seeds.
Of course you wait and do this right before you are going sow them in case they sprout.
Think this would work?Sounds feasible to me.You could use a frozen tomato to accomplish fermentation.
My brain is working great tonite, maybe I will go create something