Yep, fully understand and agree your sentiments/frustration/annoyance.
Mine blew up on the motorway at 70mph just b4 Xmas 23. After messing around with JLR BS I took a long hard look at Repair/Get-Rid options and costs. Plus, after this awful failure I had to decide whether I was still 'in love' with the vehicle and if not, how would I get back to feeling good about F-pace ownership. 2 months thinking time. For the get-rid option was offered 10k by JLR (mine cost 34K in 2022) for the vehicle in broken-down condition.
Decided (60/40) wanted the car, had zero confidence in JLR, had to avoid throwing good money after bad etc. Looked deep into suitable repair garages etc, hence SSG Prestige. All dbl super duper after that decision and repair = feeling good about all. However, I am down 17K.
On another Jag owners site there is some class action stuff going on, USA generated (I believe) where JLR rep has sunk so low that new vehicle warranty has been increased to 5 years + free servicing. I have joined that action for (some) recompense of replacement motor + turbos costs. I wish JLR Europe had that.
My experience with JLR was/is that they provide all possible help short of any actual assistance. Such and awfully frustrating/time wasting experience. I decided that life was too short to continue beating my head against their brick walls so took the self-funded repair route, promised myself to avoid JLR in future where/when possible (for servicing, future repairs etc) and started 'fighting' them as part of a wider (more powerful) lobby group.
Your 80% JLR repair cost offset sounds considerably better than many, many others. If you can get a written commitment to that figure (pref 100%) then I'd go for it. But because JLR are basically a-holes I expect the harder you push the lower the offer will become. Each to his own and good luck.