We are filing a Marijuana Limited SAR on a LLC.
Should we list the owners names and identifying information in Part I also or just the information on the LLC?

Much of that will depend on the details of the situation. That said, it would be helpful in the narrative to detail the who, what, where, when, why and how which could include mentioning the owners of the LLC.

I generally think of a Marijuana Limited SAR as saying basically, "There is nothing suspicious other than the fact it involves state-sanctioned marijuana."

If there are no red flags, I don't see a reason to include owners as subjects, especially since if it's a state-sanctioned marijuana business the state presumably has a registry of the owners. I agree with RockChucker that this information should probably be in the narrative.