Disaster

Rega RP3 turntable, TT PSU, Rega white belt, Grado Sonata Reference cartridge, Conrad-Johnson P-11 pre-amp (modified), Oppo Blu-ray player ( used as transport), Theta D S Pro Prime DAC, Cardas cables and interconnects, NuForce 9 Mono Block amps (modified,), Dalquist DQ 20 Speakers (modified).

the heart of the system is vintage:   Conrad Johnson, Dalquist, Theta.

Wishing you a speedy recovery.  I too have been recovering from recent surgery. Can't wait to get back to my system.  Very very soon I am told yeah and hallelujah.
Sorry no knowledge of about soot.

Thank you for your good wishes.
it would be nice to come one to a clean room with working stereo.

I suspect each item can be replaced with time-consuming searches and then re-modified.

Back to cleaning - some firm cleans museum pieces after fires cause soot, water & foam damage, so it should  not be impossible.

A thorough inspection will be needed.

Good Luck!

Why would you not file an insurance claim and have the insurance company either replace the damaged components or contract out to a company that specialized in electronic remediation?

If you attempt the rectify the situation yourself, you may jeopardize your ability to file a claim at a later date because the insurance adjuster may not be able to differentiate between the fire damage and the damage caused by your failed attempt i.e. you made it worse.

File a claim and have the damage on record and don't attempt any repairs etc. until the insurance company has assessed the damage.