I can completely understand the people on this thread with experience of behavioural problems in dogs coming on to ask what OP has tried, to wish to help out etc.
But in the circumstances the OP describes, to take this road is absolutely not acceptable. OP would be utterly irresponsible to do so.
There is about to be a newborn baby in the house.
It does not really matter if OP literally HAS tried everything, behaviourist etc, or whether she's an utterly irresponsible dog owner who really really hasn't.
The fact is that the dog is unpredictable and, right now, dangerous, and the risk of keeping it in the house with a baby while it undergoes more/increased training is taking a risk with someone else's baby. If the dog did injure the baby or worse, how on earth could OP live with herself?
Furthermore, while rehoming isn't ideal, keeping the dog within this home isn't fair to the dog either. More people, including a baby, are due to move in, so more upheaval - almost certainly including dog moving to a more restricted space. OP no longer wants to do the training either, and I'd argue that that in itself isn't fair on the dog either. The dog should be wanted.
I honestly think that starting down the road of 'have you tried...?' is just not fair in this situation.
OP, you need to take advice, maybe a breed charity? Fostering? i don't know, but in your position I absolutely would not take the risk.