explain florida statue 48.031?

I think you are getting way ahead of yourself. First very few personal injury claims end up in litigation and you don't even think anyone was injured. Also, if it is just a matter of property damage, the insurance companies almost always work those out among themselves.  The statute you cited is for cases in litigation. If there are issues in dispute, I would expect you will first get calls from lawyers, insurance adjuster, or investigators about what happened. Assuming you are a independent witness, what you saw should resolve who was at fault, just from your statement.  A person has four years from the date of accident in which to file a lawsuit, so in the unlikely  a lawsuit is ever filed over this, I do not wish to speculate about whether you are or are not getting your mail.The mailed subpoenas typically are for traffic court and minor criminal matters. As a mere witness, the failure to show up for a minor traffic offense on a mailed subpena, without proof of service, is very unlikely result in anything. If the matter is reset and your are given more formal service and if you ingore that, than there could be issues. There would then be a more formal rule to show cause served on you. So really, I think your worrying about not getting a subpena is premature. Having said this, do not ignore a spina to appear if you actually receive it.