When you review your proofs please read them carefully, being sure to respond to all copy editor queries, and make all corrections (including those resulting from copy editor queries) on the page proofs. The final responsibility for correcting typographical errors in proofs is yours.
I have no idea how to edit PDFs. I now understand that this can be done with the touchup text tool. The problem is that when I try that, they ask for the font. And 1) I obviously don't have it installed and 2) I have no idea what font it is, so I don't know where to get it.
As far as I am concerned, the publishers are asking me to supply information that doesn't exist, insert comments which don't make sense, and make the changes in a way which can't be done. If anybody know of a secret trick, please, please share it.