Well, if you are available, we are looking for people to fill out our team still. Obviously, we can't pay you yet, but we are closing on Alpha 1 which will mark the launch of our Kickstarter and some working capital. Feel free to send me a PM and we can discuss further.
To answer your question, no, it is not possible to use anything on the client side (anything in Construct 2) that cannot be tampered with, since all of it resides on the user's computer.