I would use a standard medium to fine grade orchid bark in the smallest pot that could contain the roots. Watering frequency depends on many factors, I would let it start to dry out a bit between each watering, I've got both species of this hybrid but I water godefroye much less often (about every 10 days to 2 weeks) than malipoense (every 5 to 7 days I think) simply because it is in a larger pot (I didn't have any more smaller pots at hand).
Good advice from Ray. To put it simply, when the pot dries out quickly increase watering frequency; if it stays wet for longer decrease watering. Many factors can influence how fast the medium will dry out, finding the right balance of light / humidity / pot size etc etc is the trick, there is no one formula but many approaches that can work and even more that won't workHow will I know if I should increase or decrease watering for it. I found fine grain pure fir bark and have perlite