You should read the court decision from mid September. Those birds should have been put down in February. The whole region now is at risk as migratory birds are passing through that area.
Not surprisingly, there is also no evidence before the court that the remaining birds are useful for any research at all, nor are any researchers even interested in looking at them. Most certainly they have not developed any type of immunity.
I’ve put down hundreds of chickens and livestock over the years. You don’t get to fool around when it comes to these things. This whole thing has been turned into a property rights trespass annd ownership issue when in fact it is a farm owners responsibility to the public issue.