The following should get you started:

use strict;
use warnings;
use File::Copy;

my @drives = qw(c: d: e: g: j:);
my @dirs = qw(/dir1a/partb/partd /dir2/part1/part2);
my @files = qw(OK.txt error.txt unknown.txt);

my $bestPath;
my $bestTime;

for my $drive (@drives)
  {
  for my $dir (@dirs)
    {
    #Assume first file is sufficient test to find all files
    #That is, all the files are in the same dir and of the
    #same age.
    my $path = "$drive$dir$files[0]";
    print "Trying $path\n";
    
    next if ! -e $path;
    next if defined $bestPath and -M $path < $bestTime;

    $bestPath = "$drive$dir";
    $bestTime = -M $path;
    }
  }
 
die "No suitable files found" if ! defined $bestPath;
  
#At this point $bestPath contains the path to the files.
#Use rename oldname, newname to rename the files.
#The time the program started can be got from $^T.

#Use copy("from", "to"); from File::Copy to copy the files.
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