Brake fires are not common, these days but should be treated as potentially very dangerous.
Certification RTO tests require five minutes after stop at maximum weight before firefighters can intervene:
https://youtu.be/f4LFErD-yls
Note no extra fuel or engine oil added, nor do I believe there's any certification test of cabin integrity for any duration of a pooled fuel fire.
The 777 RTO video notes a cost of $750K for wheel assembly replacement. Likely it would be considerably more expensive to replace partially melted engine, nacelles, wing and fuselage components from a pooled fuel fire test, but BA has not shared the repair costs of the 777 RTO at Vegas.