Muslim Property -rights Of Legal Heirs At Partition; Need Clarifications

I am trying to buy a property from a Muslim D. The said property belonged to her father(F) before her. In 1988 F had partitioned his property via a partition deed to his four pro-genies; one of them being D. Problem is that F has two more pro-genies not even mentioned in the partition deed. 1) Do these unmentioned pro-genies (1 male and 1 female) have a valid claim to contest the partition. 2) Does F have a right to leave out a pro-geny during a partition via a partition deed. 3) To my understanding maybe F could have sold the property as he pleases or maybe he could "git" the property to a few of his heirs leaving one or two out. But if he is partitioning via partition deed, then all legal heirs must be treated fairly or else he should get consent from all legal heir on the partition deed forgoing their claim. Am I right. 4) If what I said is correct; is there a solution. (like getting an affidavit or something from the left out pro-geny now forgoing their claim)