This is really kinda the crux of it.
The AI suggested the MRI not because it had some insight into "oh there's something only an MRI can detect going on", it was just a "collect more data" situation.
Frankly, the author of the blog should probably have gotten a second opinion from a different fertility doctor sometime in the intervening time period.
As someone who also went through multiple rounds of IVF with my partner, the number of ultrasounds you get during the process is immense. It's hard to call missing a peach-sized fibroid that many times anything other than gross incompetence.