This new case comes from the 2004-series V11 Sport. I have not heard of any such models having problem with cracking gearbox house.
They are 100% identical with the first 2000-models, but many things may have been changes to the better in the production.
Alu-alloy, casting prosess, bigger radius in corners etc.
Why use time and energy in trying to repair, when you can just put in a new part. I think the cost will be around the same level.
Rolf