Is it sufficient to fast for an expiation of an oath if there is money available in the bank from a scholarship grant, and is it obligatory to feed ten indigent people from this money, or is fasting sufficient?

If the granting entity stipulated that the money be spent only on study affairs, then it is not permissible to spend it on an expiation for an oath.

However, if the granting entity permitted its expenditure on study and other matters, then you have taken ownership of the money, and it becomes incumbent upon you to pay the expiation for the oath from it. Fasting is not sufficient, as there is no inability to feed.