Dillinger's escape from the Crown Point jail with an alleged wooden gun has been the subject of many debates over the years. In April, 1935 the news was reporting that Dillinger used a real gun. Director Hoover wanted to know who was making comments about the matter to the press.
An April, 1935 memo reveals the results of an inquiry on the press leak and coming on the heels of that leak, is a statement provided by SA Walter Walsh who participated in the Crown Point investigation, and the Dillinger case extensively. I suspect, as was the usual case and still is today, that the prosecutor made his own conclusion and leaked it to the press. What "appears" to have happened and what "the evidence" actually shows is always a two sided sword.
As can be seen by the memorandums, the Crown Point investigation did NOT prove anything about the gun used by Dillinger either way. The issue of whether it was real or not was opined by the witnesses. You are free to make your own conclusions based upon SA Woltz's investigation and the writings of others.
According to author Bryan Burrough in "Public Enemies" the truth about whether Dillinger used a real or wooden gun "is lost to history."
The inquiry on the leak is here with regard to SA Walsh
The statement of SA Woltz of his investigation is here: page 1