Tds on incentive/commission to non resident

Dear Sirs,

I am a new ca in practice. My doubt is regarding the certification in form 15CB (Rule 37BB).

One of my client (a hospital) has entered in to a contract with an Non Resident (foreign citizen) to canvass patients from abroad.

According to the agreement, the Non Resident agent has to canvass patients from abroad to this hospital. A fixed perecentage of the hospital bill  has to be paid as incentive to this Non Resident agent.

Now, inorder to transfer the incentive to the account of the Non Resident, they need a certificate from CA in form 15CB. My doubts are:

1. The TDS rate for commission is 10% (Sec 194H) . But this agent has no PAN Card. So, is it compulsory to deduct 20% ?

2. The Non Resident agent is a citizen of Nigeria, but the amount has to be send to his account in New York. There is no DTAA with Nigeria. Shall I consider the DTAA with USA ?

3. There is no mention about the tax on commission in the DTAA with USA. Is it possible to avoid deduction saying that there is no rate as per DTAA ?

4.Disallowance under Sec 40(a)(i) is applicable to this payment ? (that section is worded as "interest, royalty,FTS or other sum").

Please advise me at the earliest.

Thanks in advance .....

vinodaca74 @ gmail.com