I really feel for you, it sounds very hard. It is also hard as parent and not knowing what to do for the best for your child.
My dd is 3 but I'm erring on caution and no doubt will have similar worries when this baby is born.
It's a very strange time, more so to have a baby in the pandemic and then try to work out the rules and how comfortable you feel with new baby even if rules allow some things. For this I can understand her pov but the pram touching does seem a little far.. Some wipes or hand gel and washing hands would go some distance..
Are you meeting up outside in a large space and she still feels concerned?
All I could suggest is an open conversation about what childcare may look like, considering that you will have such close contact and 3 m is not too far away..
Also just keep up with plenty of video calls, he will recognise your voice and your face etc.
Babies have such limited eyesight initially and I'm sure he will get just as much from you by being in his mums arms or playing and still hearing and seeing you so I'd not worry too much about the bond.. That'll come and even with physical touch it can be hard sometimes
Depends on where you live but we haven't been really out of lockdown long, these rules loosening are still a bit new, there's media and 2nd wave worries going on.. Its going to take time to feel comfortable with many things again.. Esp as a first time mum
Just remember that this is a short time, he has your lifetime to bond with you and cuddle and play with you, you will get this relationship with him
And.. Ditch facebook