Carlos,
A partial solution...
If you put your CR2s in one directory and your processed JPGs in another directory, then open them into the *same* contact sheet, then PM will 'join' these two files (provided that they have the same filename base and that you've enabled the Contact Sheet preference "Combine RAW+JPG into a single thumbnail"), at which point you can select the RAW+JPG pairs and use Tools -> Update IPTC/XMP to sync metadata from CR2 to JPG (or vice versa).
I use this to sync metadata from NEF/CR2 to processed JPGs.
Now, I'm not sure if this will sync EXIF (I've not had a problem with my EXIF getting dropped), and I'm not sure if or how this can be used to update a (processed) TIFFs metadata from a raw file, so it doesn't answer your question completely.
Chris