I don't know enough about L2 HGA except that it is inherited through the DNA. Unfortunately it is in her family line inheritance, and there is not much can be done about that other than give her the happiest life ever, and follow any protocols for management suggested by a trusted vet.
Inflammation of the scar after surgery can happen. I know. My own dog had that but it was just redness and slight swelling around one part of the incision area, and it went down within a couple of days. There can also be a reaction to the sutures used. So long as there is no sign of infection or other general loss of condition, that in itself doesn't have to be too worrisome.
But of course, keep an eye on the incision area. If it continues to weep, bleed, or shows any pus or signs of infection, or if her temperature is up, or she seems 'under par' in any way, get her back to your vet immediately