That is the conclusion I came to as well. If you are worried either utilize an oil change analysis program or halve the recommended OCI and call it good. Or suck it up and buy the oil they tell you to.......or disregard your warranty completely and do whatever the heck you want.It looks like the only difference with the MS-12991 rating is that it is low ash which is designed to help with DPF issues. Regardless of what oil you use I would just change it earlier than recommended.
That's a lot of "or's"