Quoting Vivian [♥]:" First off, call someone to come pick up Sheldon for a few hours. But I'm so sorry you are going through ... [snip!] ... when he gets like that, once he gets better, you can show him? Kind of hard to deny something when it's right in front of you."
With him being schizphrenic and in denial, I can see that backfiring horribly. It's a good thought, but I don't think it would be wise to execute.
So sorry you are going through this. I've been down that road too many times myself (I'm schizoaffective). It is so hard to accept that something is wrong with you whether it is mental or physical. It's so much harder for men.
I hope he gets the help he needs and goes without a fight.
If you can't find someone to watch Sheldon, I suggest trying to get him to take a nap with some white noise in the background shortly before they arrive. I'm sure you can ask for a phone call in advanced if you call explain that you'd like to be able to put the baby down for a nap before everything hapoens.