Well, this isn't very strong for the pro-conspiracy side; Lea McGown cannot say for sure there were two other men in the room (one voice "could have been a TV"). She never saw McVeigh with anyone else and couldn't identify "John Doe #2." Not good for the pro-conspiracy view.
Hilda Lopez and Tom Kessinger are a little better, but Davis did serious damage to the conspiracy position.
If this is all Nichols has, then the "John Doe #2" defense isn't going anywhere.
Jayna Davis's book The Third Terrorist is a must read. So much more evidence than I ever thought. There are 23 witnesses to John Doe #2 who is identified in the book (not Jose). The people who back up the evidence in Davis's book is impressive.
The book is an excellent read; I can't recommend it enough.