Suspect that the whistle blower obtained a hard copy or screen capture of the relevant documentation and Comer has it in his possession. The doc was not classified so it was available.
There has been a lot of play about the fact that the doc was not classified and Comer is making the point for several reasons. .
Hopefully, Comer is playing the FBI and Wray to get them to bite on charges of a cover up and obstruction of justice.
This case will never see a court of law so it will be tried in the court of public opinion
IMHO, Comer is setting this up for trial of public opinion to make Biden, the DOJ, the FBI and Wray look as bad as possible.
Can only hope