That is the exact same standard form letter I posted. The seeds lacked proper documentation and they were seized. You can collect all the seizure letters you want but absolutely nothing will come of it. There is absolutely nothing that can be done and any lawyer worth anything will tell you the same thing. If they're not then they're just stringing you along to collect a fee.
I don't understand why you are spending time on this. The rules are clear. Agricultural products require proper documentation to be imported. Those rule exist for a reason. It's not just the United States, almost every country has import rules that are supposed to be followed.
There is absolutely nothing you can do. Any lawyer that you're talking to should know this. I hope you're not paying anyone for a fruitless attempt at arguing your seeds were confiscated without cause. There is absolutely no legal recourse that is available to you. It's time to move on.
I use absolutely numerous times to make a point. It's absolute that there is nothing you can do.