if you have the ClothNurb (or ClothSurface depending on your version of C4D) Baked to PLA you should be able to choose all the PLA keyframes and do a Functions Move/Scale in the Timeline window. Set the Scale to something more than 1 and it should stretch the keyframes evenly out.
I think maybe the cloth tag is still controlling the mesh welding, so if you delete the tag the points are still moving the correct fashion but the program has no way of knowing where the tearing should occur.
I think PLA doesn't work as expected with cloth and tear since with tear enabled new points are being created so the polys can separate but not loose any geometry. The only reliable success I had while testing was to do the cuts on an object, select the polys and Disconnect them all, then add Attractor and Cloth tag but don't use Tear. You don't get parts that stick together that way, just all the polys exploding away from the Attractor but the PLA and slowing it down works properly.
I've been successful using xreTime with an exported alembic sequency with subframes enabled... but as allways the more frames you've got to begin with the better. I ended up time reversing a cloth explosion to recreate it's casing, and it was a pain to get it going until I've figure that out.