Translation:The priest forced the father to abandon his daughter.
Isn't the third-person singular past tense of "sētegon" "sētetas" and not "sētas"?
There are many types of composite causative verbs in High Valyrian, but the verb "sahagon" can be used for any causative construction. The verb is conjugated normally, with the causer being assigned the nominative case; the causee (the one forced to act) being assigned the dative case; and the other arguments being assigned their natural cases.
For example, contrast these:
Azantys zaldrīzī idakotas. "The knight attacked the dragon."
*Dārys azantot zaldrīzī idakogon sētas. "The king made the knight attack the dragon."
In the present tense, "sahagon" has the stem "sah-", and in the perfect, it has the stem "sēt-".