Is it the right of the executor or of the administrator of the deceased‟s estate to pay the heirs?

Answer

In fact the executor himself should be the administrator according to the Shariah. If someone is required to assist with the administration of the estate, he will be a mere employee entitled to a wage. But he has no authority to override the executor. In the case mentioned by you, it is an upside down scenario. Instead of the executor controlling and paying the administrator a wage, it is vice versa.