How can the FBI, match DNA to highjackers, that are supposedly still walking around alive, and are suing the government to clear their names?

And your proof of this ridiculous claim is what?

9/11 Misinformation: Flight 'Passenger Lists' Show 'No Hijacker Names'
• Misinformation: Passenger "Manifests" Contain "No Arab or Alleged Hijacker Names"
• Passenger Manifests versus Victim Lists
• Who Had Access to Flight Manifests on 9/11?
• When was the List of Alleged Hijackers Finalized?
• What about the Security Videos?
• Other Problems with the Hijackers
• Conclusions

Hani Hanjour existed and spent much of the last 10 years prior to 9/11 in the USA.

Here is the official info about these "hijackers". Many of the real identities are still alive. The FBI ignored these facts during 2001-2002 and never updated their suspect list.
"Official Pilots":