I have had your circuit as my "target" in MDWS from the day of your initial post.
At my initial look, the only thing which stood out was the the "fine-tooth flea-comb" effect in the DS1 & DS2 bands of the QLN plot. Seeing that makes me suspicious of the AC balance of the circuit.
Following your second post, I took another look and captured two images . . . that of a section of the recent SNRM plot and the QLN plot. (Attached below.) Seeing them both, I am inclined to say that there does appear to be a defect in the metallic pathway.
If you are certain that there is physical tree - drop-cable interaction, then some tree surgery would be appropriate. Depending upon the cable's condition, it may need to be replaced.