Well, actually the problem is with Mailjet: it seems like there’s something in the “from” field that doesn’t match their requirements.This is why I wanted to have a look at how the emails are created and try to identify the problem.
Thanks for your answers. Actually, he /members/me/profile/dashboard works (I do have a dashboard that’s not the WordPress one but rather one I can edit with some of the info from Buddypress).