Ela sounds like Elas (plural)
I just reported the audio because of that. It isn't the first time this happens, either. :)
Why is there a "de" here? I thought de was not necessary when gostar is followed by a verb
Always use "de" after gostar.
I was thinking of 'precisar' I think
Yes, although I do not think it would be considered wrong if you included «de» after «precisar». At least, in European Portuguese, it is done all the time.
Exactly. In Brazil, we use "de" after precisar only when it is followed by a noun, but in Portugual they always use "de".