Lower eyelid retraction after surgery
There is right lower eyelid retraction, likely due to contracture. Surgery can be done to raise the lower eyelid; see following link. See an oculoplastic specialist experienced in this work.
Scar tissue eyelid
Laser treatments and injections of 5-fluorouracil can be used to relax and soften the scar tissue. I would not advise more surgery/cutting at this point - just scar treatments. Fractional co2, pulsed dye laser and non-ablative fractional laser are commonly used to help scar tissue.
There is much more going on here.
As you know, your situation is very complex. It is for this reason, that many surgeons do not recommend orbital decompression for 2 to 3 mm of proptosis. The potential benefits must out weight the risks. In comparing these images, there appears to be very little if any change in the axial position of the eyes. It appears that an infracillary incision in the right lower eyelid was used to access the orbit. This is not a standard approach. Most of this work is done through a slinging eyelid, transconjunctival, or transcaruncular approach. Revising the scarred eyelid involves interposing grafted material between the bone covering (periosteum) and the eyelid tissue. The vertical height of the lower eyelid is also compromised and this needs to be addressed. This is very specialized work and you need the right surgeon.
Lower lid retraction after orbital decompression
Lid retraction may occur with onset of thyroid ophthalmopathy or after surgical procedures on the lower lid, or after orbital surgery through an incision in the lower lid. Medical therapy alone is generally no match for the powerful contraction of scar tissue that tethers the eyelid to the bone of the inferior orbital rim. Steroids or other medications to inhibit scar formation may be helpful adjuncts to surgery. Theoretically, Plasma Rich Protein injection into injured or inflamed tissues supplies the body's own growth factors to assist with the healing process and has been used for various sports injuries. Randomized double-blind studies to confirm beneficial effects for eyelid retraction or postoperative scar tissue bands are not available. The traditional surgical techniques releasing scar tissue attachments, elevating the lateral canthal tendon, grafting to the anterior or posterior layers of the lid, splinting the eyelid or putting the lid on upward traction are the mainstays of treatment. 5-fluorouracil and mitomycin C are considerations to prevent exuberant scar tissue, but dosages and exposure times for use in eyelid surgery are not well-defined. After 4 surgical procedures, it is wise to seek multiple opinions from experienced oculoplastic surgeons.
Scarred lower lid
PRP is not going to help with deep scar tissue. Better options are injections of 5-FU and steroid. These are usually given early in the healing phase, especially in someone who has a tendency to form a lot of scar tissue. But even later on, these may help to soften any scar bands. Unfortunately orbital surgery is not easy, and sometimes implants need to be adjusted or removed. With every surgery you can get more scar tissue, so it becomes more difficult to do revisions.