I'm not too sure if you can do much in this case. It is fairly normal to take solicitor fees out of the estate prior to funds being distributed. As your brother was left the bulk of the estate, it probably would have been nice of him to have covered the solicitor fees...nice, but not obliged. He is also entitled to claim for necessary expenses, but he is not allowed to profit from being executor.
However, as benificiaries, you are entitled to see accounts of the estate and all the paperwork (afaik). If your figures are correct for the value of the estate, the figures seem to be approx correct (but it means he took expenses of almost €2400....which seem high). You could ask him for the accounts, the grant of probate, solicitors invoice, etc. and review them all, but bear in mind it may cause a rift.