Photographer here (mostly food), and I agree, you do not want to leave your camera/phone unattended, especially for a precious moment like this. Whether it’s shot interference, or even someone wants to take the camera. Maybe consider hiring a photographer, or a trusted friend to help!

Brooklyn Botanic Garden/Wave Hill/NY Botanic Garden can be great spots, but you’ll have to most likely pay/set up a permit for the pro-style photo shoot. Jefferson Market Garden’s a bit low key (& tiny) so you can maybe get away with it.