Agree with most of what Bntnail shared. Few of the problems presented in the radiographs can be "fixed". Bone remodeling is forever.
Comfort is the goal and best nominal hope.
Focus on phalanx/hoof capsule alignment and sole depth. The "high heel, no toe" you described earlier is correct for this horse. Reduce as much DDFT pull and toe leverage as possible.
Generating sole depth will depend largely on any remaining functionality of the vascular bed. A venogram would provide a baseline for future reference.
Silicone is a poor choice for this horse; doesn't take two days to setup and should not require duct tape left on that long to address. A softer impression material or pour-in pad would better serve this horses need. Silicone is too firm. Include an antimicrobial to avoid soft tissue intrusion by opportunistic bacteria.
Frog support is an important aspect of management in a case like this.
... And no, we have never had a foundering problem.
Yes, you have. Your horse is currently "foundered". Chronic, mechanical laminitis. Shoeing protocol should include management for that condition.
Medial/lateral displacement of distal interphalangeal joint is significant. Wolff's law of bone remodeling intervened and remodeled the condyles to accommodate that imbalanced load effect. Shoe for medial support as much as possible.
Yep... she's a train wreck and been that way for a long time. It will take some pretty creative (translation: expensive) management just to keep her pasture comfortable.
Heartbar shoe; elevation as necessary to assure post-trim phalangeal alignment; heavy roll at the toe. Soft to medium pour-in pad with copper sulfate crystals in back half of foot. Short term Magic Cushion in front half to encourage sole growth. Mesh and leather to hold the whole thing together until some improvement in sole depth followed by long term full pour-in pad (vettec soft with antimicrobials). If the skills are there, a roller motion (banana) shoe with frog support might be a better long term solution than a generic heartbar. Let's the horse find it's own best comfort caudal elevation.
Best luck and, as always....