MLP K-1's are complicated and without being able to read all of the details that are typically provided along with the K-1, it is hard to respond to your specific question.
Section 1231 gain, in general, is taxpayer favorable and treated as capital gain. As a result, is not included in QBI. However, if there is Section 1231 recapture as a result of prior Section 1231 losses, then the Section 1231 gain, which is generally capital gain, is recharacterized as ordinary income and is included in QBI.
As a result, I concur with @Mike9241 and just input based on what you have even though you can't reconcile any difference. You just need to rely on the premise that the preparer of the K-1 understood the complexities and what is presented is correct. These K-1's are typically prepared by top accounting firms that know what they are doing; although they do get amended from time to time.
*A reminder that posts in a forum such as this do not constitute tax advice.
Also keep in mind the date of replies, as tax law changes.
