from what I have seen the DangerousThings / Vivokey implants are MRI safe. I even read about someone with a Titan magnet in there finger getting MRIs and not having any problems.
https://forum.dangerousthings.com/uploads/default/original/1...
as for the Titan Magnets I was just referencing this post
https://forum.dangerousthings.com/t/fingertip-titan-in-an-mr...