Since the markers are jittered then you will have to describe just what the actual "problem" is.
I suspect that you have an expected appearance but you don't say what that would be.
This from the documentation on the WIDTH option for JITTEROPTS may apply:
Note
For a discrete axis, this option has effect only when the markers cannot be clustered side-by-side without overlapping. When WIDTH= is set to a value that is sufficient to eliminate marker overlap in that case, increasing the value further has no effect.
You have specified the x axis as discrete. If your issue is the odd vertical dispersion of markers I suspect the procedure is attempting to avoid overlapping the markers in both vertical and horizontal. Also o character has more area for overlapping than + so things move further apart to avoid the overlap.
And without any data we can't test your code for modification. From your display I would guess that Trt A has more records with similar Y values.
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