Tier 2 Dependent Child - Question about Admin Review

Just wondering if you guys could help with my situation. My son's application as a Tier 2 General Dependent Child visa has been refused stating that i could not prove that i have the sole responsibility for my son.

The refusal letter states that i can request an administrative review but the form to request a review or an address to send the request have not been attached with the refusal letter. The application was made in India, have anyone used the administrative review ? there are form for administrative review available in gov.uk website, can this be used?
Can anyone point me to to an address(physical address, fax or email) where this form could be sent ?

I have already sent the questions to home office and waiting for a reply, in the mean time any useful information will be helpful.

What is the status of the child's other parent?