Morning, Brian. Hope this post finds you well.
There is a first time for everything they say.
I like to turn to InspectAPedia ® for rules and standards.
1: Clearance is suspect. 1" inch for B vents but the manufacturer has the last word. Hard to do without a label.
2: Draft hood style/type and connection.
Did you try to move the draft hood to ensure it was secure to the water heater cabinet?
3: Flue support. I do not observe any hanging support straps for the flue pipe.
4: Flue Slope. The vertical flue run is not sloped.
Got some great posts from members.
Thanks for sharing.
Gas Water Heater Vent Codes & Standards