For immigration law in Florida we have been using
Larry J. BEHAR in Fort Lauderdale. He is not cheap but is very well connected and I know he has been very successful with complicated cases. Yet, choosing a lawyer should not only be based on a recommendation off a public forum, proper due dilligence is recommended.
Is your uncle a veteran? Does he still have ties to the US army (buddies and superiors)? Is there a risk that his SS-debt may be routed back on any fraudulently obtained SS-benefits? These may be questions you do need not to respond to on a public forum, but to which you may nevertheless consider preparing yourself to respond to, to your lawyer and eventually US government officials and the courts.
I would also think that it is mind boggling that a foreigner could sneak into the US army only 30 years ago, a fact which may take some of the responsibility load of your uncle's shoulder, one would think.
... J-D.