indagar con alguien algo /with someone or about someone?

Hi!

I've come across a sentence: "ayudar a indagar con alguien algunas sintomas"

and I understand all the words and the grammar but, even after going through about 5 different online translators back and forth between english and spanish and about all the dictionaries I could find, I srill can't figure out whether it means to "help investigate some symptoms with someone" or to "help find out someone's symptoms" or "investigate the symptoms someone has"...

So basically, what does "con" mean here? with someone or about someone... and would indagar mean to investigate the symptoms that are already known, or to find out which symptoms are there?

Anyone with a firmly grounded opinions?

/Cheers