That will make it worse.
Being below the arms isn’t as bad as being on top but it’s still bad. I know a lot of people do this but they should consider themselves lucky if the radio still works well.
Many radios use metal which is not physically connected to main part of the antenna to boost the signal. This extra metal (or carbon) needs to be just the right size and in just the right location to boost the signal or otherwise you’re likely to make the signal much worse.
The batteries would likely also shield the batteries but it might not be as bad as the carbon.
Ideally you want some sort of plastic or wood rod to hold the antenna away from the rest of the quad. I’ll try to find some photos of good examples and post them here.