Sale of property through General POA (without consideration)

Dear Sirs- I am in the midst of buying a resale property in Pune. The owner A resides in USA and has therefore appointed his father B as a General POA (without consideration) to deal with matters of the house. This general POA is registered with the sub registrar CL II Haveli 15 Pune. One section (of many) states 12. “in the event, executant desires to sell/transfer the said flat to the intending buyer a. To negotiate with excite and enter into memorandum of understanding, Agreement, Agreement to Assign, Transfer, sell, deed of assignment, correction deed, cancellation deed, transfer or any other documents, transferring the rights of executants to the intending buyers. My question is whether this transaction is acceptable. 1. Can the general power of attorney B sell the property to me on behalf of A 2. Since it’s a registered document, does it circumvent any specific law 3. Index 2 has the name of person B as the general POA who has executed the transaction at the time when the property was bought, so is this ok In essence all I want to understand is, if I buy this flat, can person A at a later stage dispute the sale?