I'm not going to meet in a park or dog-friendly place, as I don't want him near baby or trying to put his head in pram!
I think this is extreme and indicates you may need some help getting over your fear. Your cousins dogs is likely to be around for quite a long time in your family, and a sensible introduction in a neutral location now is likely to mean a much more pleasant relationship in the future. A dog under the owner's control, assuming it has been well trained and socialised, is not going to snap, just from sniffing a baby. They're likely to be curious, interesting the new smell, and they will want to use their nose to investigate this new thing. A calm introduction, let him have a quick sniff, then praise him for being quiet and settled. Most likely, at baby age, once the dog has satisfied it's curiosity about this new thing, they'll be off for a run around the park and more interesting pastimes.
Making a big deal out of the baby and getting freaked out when a dog comes near you is the worst thing you can do. If the dog comes up and you're shrieking 'get away, get away!', waving your arms and trying to pull DS away, the dog will think that you're playing and will want to know what that exciting toy you are holding is. Make it very boring and the dog will care very little about your DS.
I brought newborn DS home to a house full of six dogs. As soon as I got home, I put DS in his cot, sat on the sofa, let the dogs in and then greeted them. After a few minutes, I picked up DS and sat back down. The dogs came over, had a few snuffles over him, and were told to 'sit' then praised and given a treat. Within five minutes, DS was basically forgotten and they went off to their usual spots for a nap. This was basically routine for the first few weeks of his life. He was never left unsupervised with them, and never allowed to crawl on them or annoy them. As such, they have never been in the position where they felt they needed to defend themselves against him, and life is peaceful (well as peaceful as it gets with six high drive dogs and a 4 year old in the house!). The relationship between them is lovely to see, and he particularly loves getting in the whelping box with a bunch of puppies and letting them play with him.
It's naturally to want to protect your child, but you need to be sensible and not let your mothers protectiveness turn in to a phobia. Dogs very, very rarely are genuinely aggressive. The majority of dog bites are because the dog has been provoked in some way. We've all seen those 'cute' viral videos of kids laying on top of dogs, pulling their ears, trying to ride them, and I just want to scream 'get the kid away!' because I can see the signals the dog is giving out. Dogs will warn before biting and they may not be signals you would think: ears back, yawning, refusing to make eye contact, are all signals that the dog is uncomfortable. Don't put the dog in that situation, and the chances of biting are almost non existent.