Boot sector info: Grub2 (v1.99) is installed in the boot sector of sda2
and looks at sector 131415765 of the same hard drive
for core.img. core.img is at this location and looks
for (,msdos2)/boot/grub on this drive.
=>not fully correct if I read right.
search --no-floppy --fs-uuid --set=root c44d0292-2966-4537-bbe8-4603b3de2c48
it simple searches for a partition with UUID c44d0292-2966-4537-bbe8-4603b3de2c48
That's unique so it doesn't matter where to put the partition and UUID is part of the partition. For example you can move/resize partition. Or move it to another physical harddrive by doing a copy/delete. This partition boots on its own for sure as long as it marked ACTIVE.
But now it is NOT marked active!! NEOGRUB entry in win7 bootmgr just does a search for file core.img in folders like /boot and /boot/grub on ALL partitions. And if found it loads and runs that volume bootsector (that's called chain loading). It acts like it was marked active.
The volume boot sector is just the first sector of the partition (first 512 bytes) and is backupped and restored.
So no problem at all!!
Who the heck did clean first sector??? Of course you don't know. Try to backup/restore linux again and see if I'm right (I am LOL). If not you can always repair it the same way I told you before