Once there is a solicitor handling the probate and distribution of the estate, he will handle all the money. Nothing (money) will go through the executor. So once all the assets are gathered the solicitor will pay all the bills, like the funeral, etc. Who ever organised the funeral gets paid when they give the receipts to the solicitor. If the executor is owed money he presents the bill and receipts to the solicitor. He gets paid. Then the estate is distributed. If the executor is owed money he will be paid but he cannot imagine a figure out of his head, he will have to supply details and proof. The money from the house sale will go to the solicitor, not the executor.
I am sure as a beneficiary you can request a statement of account to ensure you have been given the portion you were due. The executor is correct that all bills and money owed is dealt with first.
So say there was €100K and 2 children inherited equally. But the brother paid €5K for the funeral and €5K to the estate agent. He gets €10K to cover the money he is owed. Then the brother and sister get €45K each from the estate. So while the sister might have expected €50K the expenses and bills were paid first.