I agree with you to a large extent. Seems she had some contact with him before; and perhaps she might have had a good shot of getting it to him based on that past connection. She might have had a reasonable hope of getting a letter through - and who knows, he might have called her, the way he operates.
That said, she does give voice to a degree of anxiety which is out there - and it is a message I would hope is somehow getting through to him by some means.
What you say about the pope being picked by the Holy Spirit is true; it must also be remembered that while the pope is protected from teaching error - it doesn't mean he will be wise, the best administrator or example. There have been a number of popes in need of correction of one form or another; and where subsequent popes had to clean up the messes predecessors left behind. There have been some "disasters" as popes; but the wonderful thing is, the Holy Spirit protects the Church. Now, I am not saying Pope Francis is one of those potential "disasters" - but we have been relatively spoiled in the last couple hundred years with a string of good popes.
Does the Holy Spirit pick the pope? Ratzinger didnt think so. - See more at: http://www.patheos.com/blogs/deaconsbench/2013/02/does-the-holy-spirit-pick-the-pope-ratzinger-didnt-think-so/#sthash.DLDcLQeH.dpuf