Unfortunately, the pragmatic solution may be to stop pursuing it. They clearly aren't willing to compromise which means that if you want to pursue it you may have to sue them. At that point the costs of continuing to pursue the matter will most likely exceed the cost of buying yourself a new jacket.
The only people who can do the day-counting are your lawyer, the ADA, and the judge. Nobody else can have anything useful to say about it because it's so dependent on all of the facts and circumstances.
In this case I think you would be wise to consult, at least briefly, with a good attorney in your area. I say this for two reasons: first, whether a buyout should be offered at all and, if so, what the buyout would cover and what the better terms would be, will depend on all of the facts and circumstances; that is not a discussion you can, or should, have online in a public forum with lawyers whom you have not retained.
Second, the situation as you've described it raises potential issues...
Short answer: no sale agreement is going to prevent the IRS and GA from coming after you if the taxes remain unpaid.
If the unpaid sales taxes and payroll taxes remain unpaid, then the IRS and the state will almost certainly assess those taxes out against the individuals who own and/or control (or have a duty to collect and remit taxes for) the corporation, and who occupied those roles at the time the delinquencies occurred. Since you were an owner of the business at the time the...
If you had a really good attorney who handled traffic tickets you might; however, given your record, the odds are not great. I strongly recommend you speak with a traffic ticket attorney in the area immediately.
If somebody signs your name to an agreement without your permission or consent, then the agreement does not bind you. If this is a serious problem for you, I would strongly recommend you speak with an attorney in your area who can review the entire situation with you and advise you on practical steps you can take to protect yourself in case something like that were to happen.
The most direct way to get things moving is most likely to start a probate proceeding for the estate and ask to have letters of administration issued to you. Unless he comes forward with the wills, the court could issue letters of administration to you, which would give you the legal authority to administer the estate. You should also be able to get a court order compelling him to file the wills.
You should consult with a probate attorney in your area who can evaluate the situation and...
Yes, you will pay tax. If you are a nonresident alien, then the buyer will be required to withhold tax from the sales proceeds unless you have received the appropriate certificate from the IRS excusing that withholding, or the proceeds are below a certain amount.