I know how frustrating this has been for you and your family. Just like many of us here, I've been in the same situation.
What I would recommend is that you wait at least until your security screening hits the 2-year mark, and if there's still no progress by then, you put in another ATIP request with CBSA to see if your file has been worked on at all for the last 6-12 months. If you see no active movement, then that'll be a strong case to file a writ of mandamus. Anyways, that was my game plan after reading a bunch of forums and getting some AI help. A couple of weeks ago, I learned thru my MP that I was cleared by CBSA after undergoing the A34 for almost 25 months.
Good luck!
