@rose3279 Imo there is a serious lack of companion dogs with good temperament so I personally think people with healthy dogs with good temperament should be encouraged to breed. But, it should also be done well.
Nice of your friend to help you along to navigate health testing! Hips and elbows definitely should be done. I'd personally go with Pennhip, but OFA might be more accessible depending on where you live.
Unfortunately, I don't have any direct connections for you. I may breed in the future and my 'prospect' is a mix, but a golden/bernese is not what I'd be looking at hahahaha.
But there are a few companion cross breeding programs who may be interested! As some mostly outside of dogdom, connecting with them might be easiest through the FDC.
There's also a bernese outcross project. Because purebred bernese health is pretty awful. And well, so is purebred golden health.