I don't know about the sports psychology route in this case, but I'd wait for the coaches' books. We're talking about less than a week without the jump, give her time to get it back before you consider her a head case. I know she's saying that she's afraid to fall, but I think that's just to get you off her back. She's probably more frustrated than afraid and it's okay to acknowledge that frustration. Working through it is a valuable life lesson.
It's totally normal to start landing an axel or double, then "lose it" for a few weeks or months. Happens to most skaters, especially if there's a growth spurt involved. The jump will come back if the skater keeps working on proper technique and doesn't tense up.
I agree about not using the harness during this time since it can become a crutch, and later an obstacle, for certain jumps. The coach isn't a puppeteer, preventing falls, they just help prevent the falls from being as severe.
The reason skaters can land a jump on the harness unassisted, but not off-harness, is often that they correct their posture when the vest/straps are on their body. They know that the pulley rope goes upward, so they straighten their spine automatically and take a deep breath/hold it.
I would suggest limiting the axel practices to a few attempts, off-harness. Have her focus on on walk throughs and completely proper technique when she's not on lesson.
Similar situation: skater with a double salchow - had it briefly, lost it, tried for months to get it back to no avail. (In the harness, it was a thing of beauty, lol.) In that case, growth was definitely a factor, so strength training was increased and they changed jump coaches. The skater landed the double sal about a month ago and within two weeks had landed two other doubles. Sometimes, you just have to shake things up.