Disclaimer: This response contains my views and opinions expressed and not R&D's or company's.
1.How do I ensure this kind of mapping?
Each of your colleagues may be represented by a remote thing in the platform which is bound to a virtual thing in the edge SDK.
2.Should I make use of Infotable? In that case, how would it help me?
You can directly use the primitive properties. Infotable may be useful only if a single edge device is sending all the data. In such a scenario, you may use an infotable and then explode it to multiple things on platform. However, this will call for more code and it isn't as elegant as using primitive properties.
3.Should I write multiple things and pass data to each thing? in that case, how scalable this approach would be. Like what if I have to scale this for my entire company? WillI have to go and create 10K things?
Using multiple things should work. The scalability depends on how frequently the data will be refreshed. There are several ways to achieve the scalability, there are several discussions about it in thingworx community.
Shreya, since you're going to use four common properties across all users (Things, in this case), what you would need to do is use a ThingTemplate based on the RemoteThing. Any Thing you create based off this ThingTemplate is going to get (inherit) any properties or services attached to the ThingTemplate. You can add your four properties on a ThingShape as well, and then add that to the ThingTemplate (so the Things based on the Template would still get the properties).
From a display perspective, since you have them based off a single Template, you can call a service like GetImplementingThings on the Template, which will list all the names and properties of Things based on the same. You can bind this to a list widget (to display the name and select the user) and use other widgets like the Gauge widget or a Shape widget to show the data.
Is there anything specific that you are looking for? With the EMS, we include a Sample and an Example lua templates to add properties onto the platform. Click here to get to the Getting Started with Lua section in our Edge Help Center.