No, this is not flagged, if what you mean by flagged is an item that draws IRS attention.
The notation *STMT in Box 20 is to make you aware there should be a Box 20 statement attached to your Schedule K-1. Code Z is for Section 199A information.
Generally, you may be allowed a deduction of up to 20% of your net qualified business income (QBI) plus 20% of your section 199A dividends, and qualified PTP income from your partnership.
This can be a significant deduction, so you should check your Schedule K-1 carefully to see if you have a statement with the figures that you need to claim this deduction.