This is a question about capabilities. I'm not asking for a "how to".
I have aclient with the following needs:
Is Filemaker pro capable of this?
You are talking about a Multi Gigabyte database generated from mulitple computers with probably less than computer savvy users.
Equiping 1600 people with a copy of Filemake would probably exceed your budget by an order of multitude.
I am unable to point you in direction.
Maybe SalesForce.com, very maybe.