Such conversations often lead to settlement.
However, you should be wary that the opposing side might be getting coached by their attorney. Before making a final agreement be sure to have your attorney review the terms.
You can usually amend a complaint to add new claims only once. A second amendment would require a motion to the court and the court's approval.
With that said, it is important to amend your complaint as soon as reasonably possible. A motion to amend a complaint to add a new claim or claims could be denied if it comes too close to trial and adding the additional claims would be prejudicial to the other side.
In Washington State there are statutes which would allow a court the ability to award attorneys fees in situations such as you've described. There may be statutes in Florida, designed to protect against the abuse (including financial exploitation) of the elderly that provide for attorneys fees.
The heirs should be aware, however, that the usual rule is that if one side is entitled to an award of attorneys fees, the other side would be as well. That means if they don't prevail, they might...
I would follow up, again. I would follow up with a phone call and then document the phone call with an email and letter. "Just to confirm what we discussed....bla bla. If I have not accurately summarized our conversation please let me know immediately."
I would print these all out. I would file a second motion with the arbitrator and ask for sanctions. Specifically, I would ask that they not be allowed to present any evidence or documents that are not disclosed. If you need the...
It means that ANY conceivable claim you might have against the other party would be waived and you would not be able to bring it in any future action. This would likely even include claims that you are not currently aware of.
You would want to dismiss the case, without prejudice. That way you can refile the case in the future. (Provided the statute of limitations has not barred your claim).
If you do refile your case in the future, you might be obligated to pay attorneys fees to the defendant for the work that was done on this case. You would need to review the civil rules for your jurisdiction to answer that.
If the correspondence is relevant or contains relevant information, they most likely will be admissible. Objections to its admissibility might be based on hearsay, confidentiality or best evidence rule.
I would recommend that you review all the correspondence to determine which ones contain relevant information and then determine if there is a specific objection to its inclusion in evidence.