The chart shows that brown rice has as much lysine as you need, and you consider that "weak in lysine"?
Yes, weak in relation to other amino acids in brown rice.
And the chart shows that every plant food listed has as much or more of each amino acid as we need.
That's has no bearing on the proportions of amino acids in a given food (eg. brown rice).
The term "complete protein" (based on any definition I've been able to find), refers to the proportions of the different amino acids in a given food. It is an amino acid to amino acid comparison, not an amino acids/per calorie comparison (which seems to be what you're comparing).
Based on your chart, I don't disagree with this statement:
"According to the WHO's numbers, brown rice contains enough of each amino acid to satisfy protein needs when solely eaten as the diet"
I do disagree with you calling it a "complete protein". Complete protein has a specific meaning, and that's not it.