The fact is that the first person pronoun is possibly interpreted de se/non-de se with respect to the matrix subject, meaning that its reference to the speaker is not direct, and it is indirect via the matrix subject.
wechsler's (2010) self-ascription monopoly does not apply to all uses of the first and second person pronouns, and actually it only applies to all the first and second person pronouns that are interpreted directly to the speaker in the context, i.e., not via the matrix subject.