The mics you have are good mics. I've used them successfully for professional recording projects. I suspect your biggest problem is the small room. In general you don't want them super near to the piano, but judging from what I can see in the video, you don't have a lot of room to play with. Have you tried opening the piano lid? Mic position will definitely have an effect on the sound, but there's only so much you can do in a small room.