"Disinfectant" had general definitions and more specific definitions. The one I used above, I didn't make up.
My point is simply this, the President referenced "disinfectant" and may not have used it 100% (or 65%) correctly. He likely had something like the U of L process, or something else that combats the virus in the body in mind, and he is, undoubtedly, being briefed on anything that appears reasonably promising. He's not a scientist and, as always, tends to try to use "lowest common denominator" language. He is not responsible for anyone who actually tries injecting Lysol, nor is he responsible for journalists who don't even care about what he meant.
On all those points, I agree with you. But it's even more basic than that. His comments were a) clearly directed at the doctors on the podium, and b) clearly in the context of things that they - the doctors - might consider investigating. The assertion that his comments can reasonably be interpreted as a directive, suggestion, or implication for any person to inject himself with isopropyl alcohol is utterly absurd.