Here's the relevant item from Rishworth:
DECLARATION
I have applied for a B777 Captain position with Air India Charters Limited (AICL) through Rishworth Aviation Ltd (RAL).
If I am successful at screening in Seattle, and I am offered a contract by Rishworths, on assignment to AICL, I will accept the contract on the terms and conditions as disclosed to me.
If after I have successfully completed the screening programme in Seattle, I am offered a position with AICL, and decline to accept the position, I agree to pay RAL US$2,000.
I acknowledge that I have read and understand the implications of the above, and I acknowledge that RAL will actively enforce this declaration and will seek full recovery and costs.
I therefore undertake to attend the screening on the above basis or incur the penalties imposed by this declaration.
Since the 4-day 'screening' includes a tech & procedure refresher and also a licence revalidation, this at least keeps away the 'opportunists' and time-wasters.
Alteon instructors and sim time are not free!