Why was Defense Secretary Lloyd Austin's hospital stay kept secret for days?

[putnam6]

I can only imagine what kept him there for that many hours.

I'm perfectly fine with him having his privacy, but hiding that he was in the hospital is a step too far for someone at his level. Even that might be understandable, but not telling the POTUS is very odd. We don't really need to know to be honest, but the White House certainly does.

I wonder if there is even a policy on that?

Did you see the letter from the press? ABC, AP, Reuters, and Breaking Defense a Defense Industry resource. Which is weird in itself. Did the other normal top media sources not want to respond? like the other networks or our top newspapers NY Times WAPO etc.  

Policy or not it isn't normal protocol in a Democratic and supposedly transparent government.