Did you sign a personal guarantee?
Have you a copy of the ccj?
is it in your name or the ltd company name?
https://cse.google.com/cse?cx=partner-pub-8889411648654839:3134625398&q=Limited company ccj&oq=Limited company ccj&gs_l=partner-generic.12...23159.34137.0.366126.96.36.199.0.0.0.308.4270.0j3j15j1.19.0.gsnos%2Cn%3D13...0.10977j7667391j19...1j4.34.partner-generic..19.0.0.OY00NBTWR3U
Admiral probably won't offer near £3600. They are most likely to offer lower end of value shown in Glasses guide. Then you will have the excess deducted from the amount.
Always up to policyholder to negotiate the market value by providing evidence of similar cars for sale locally. Details of condition of the car pre accident etc.
Depending on the damage you can always get a local garage or AA/RAC to carry out an inspection and report on damage/costs of repair. But they may charge you and the Insurers won't cover costs of your inspection report.
Insurers don't mess around with repairs over a certain value, as can be a pain, as they would be liable for more repairs if policyholder unhappy after initial repair or damage was missed.
The £100 injury cover i thought was not cover for actual injury. I thought this was cover if you incurred costs due to be injured e.g. ambulance call charge.
Cannot really criticise Admiral as what you have been told by them appears to be correct. Unfortunately most people don't realise how Insurance works until they need to claim.
Don't touch them owe me £500 since January 2019 make excuse after excuse. Seem they always have software problems sending money out. Keep saying they will call back or email nothing been chasing it now for 6 mths the phone staff always have the same banter we will chase it up and get back to you then nothing!