I see the Ystradgynlais Family History Society do look-ups for burials at Gorof Cemetery. Here is a link to their site:
http://www.ystradgynlaisfhs.co.uk/sserv.htmlMight be worth contacting Powys County Council either on their website :
http://www.powys.gov.uk/index.php?id=1&L=0or at their Brecon Office which is: Neuadd Brychioniog, Cambrian Way, Brecon, Powys LD3 0HP
You will see on that website if you put in a search on Ystradgynlais Cemeteries that they give a list of the ones they manage but that does not include Gorof. I've looked on the Swansea City Council website and can't see that they have responsibility either, but presumably someone is cutting the lawns, keeping it tidy and holding all the records.
I'm so glad that you felt good about seeing that aerial photo; sometimes we have to go on a quest to make things right about things which have happened. I have no doubt that you will achieve what you have set out to find! I am so pleased to be able to help in a very small way to get you to where you need to be.