If it got better from the antibiotics, it is not likely fungal.
Fungal infection of the middle ear are rare.
Make sure an infected tooth has been ruled out. This is often missed and will swell the jaw.
An x ray and exam is needed.
I suggest that he see his dentist, and an ENT specialist at this point.
This sounds more complicated than a common ear infection.
A swab/culture of anything coming out of the ear, or of the middle ear is now a good idea.
This would confirm that it is not fungal.
OK, so that is an initial answer….
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