Hold up… You thought maybe you downloaded malware (which in this case that was not the only cause) so you took it upon yourself to reinstall windows on a company issued laptop?
Why are you trying to fix it? Submit It ticket and it’s their problem.
If you suspect malware alert it security immediately. Many malware act as a gateway to lock other systems. Yes you might get in trouble but I’d rather be yelled at for downloading something then yelled at for infecting my company servers will ransomware/malware.
Atleast in my company a computer connecting without a company supplied image of windows will be denied. Completely understand you not connecting to the internet.
This problem was not caused by you but could of been… Take this as a lesson to be more proactive in the future.