I am So sorry to hear of your Dad's diagnosis and then Mets. That is a really tough call. I hope you all have good family support and are being steered towards counselling, as these diagnoses really muck with the brain.
If your Dad is computer savvy, he would be able to join the Private Mens Group here, where he could chat directly with other men going thru similar treatment xx Group: Men living with breast cancer | BCNA Online Network
It wouldn't hurt to get a 2nd opinion (I changed Onc within 6 weeks of meeting him ... )
Also, Consider recording all your appointments so that you can go over them again later, as it can be difficult to take everything in at the time.
Take care & wishing you, your Dad & your family the best xx