Does a combination of both dual and solo hours in a complex aircraft (PA28R-180) which total 10 or more flight hours meet the commercial pilot training requirements of FAR 61.129(a)(3)(ii) or must all the hours be dual instruction?
As you already noted, 61.129(a)(3)(ii) says "training" (emphasis mine):
(ii) 10 hours of training in a complex airplane, a turbine-powered airplane, or a technically advanced airplane (TAA) that meets the requirements of paragraph (j) of this section, or any combination thereof. [...]
Here's the definition of training in part 61, per 14 CFR 61.1:
Training time means training received—
(i) In flight from an authorized instructor;
(ii) On the ground from an authorized instructor; or
(iii) In a flight simulator or flight training device from an authorized instructor.
According to that definition training always requires an instructor so there's no way you could log solo time as training time. All 10 hours must be dual instruction.
It has to be dual instruction per 14 Title CFR PART 61.129:
§61.129 Aeronautical experience.
(a) For an airplane single-engine rating. Except as provided in paragraph (i) of this section, a person who applies for a commercial pilot certificate with an airplane category and single-engine class rating must log at least 250 hours of flight time as a pilot that consists of at least:
(3) 20 hours of training on the areas of operation listed in §61.127(b)(1) of this part that includes at least—
(ii) 10 hours of training in a complex airplane, a turbine-powered airplane, or a technically advanced airplane (TAA) that meets the requirements of paragraph (j) of this section, or any combination thereof. The airplane must be appropriate to land or sea for the rating sought;
So the 10 hours of a combined complex, turbine, and TAA time must be in an airplane and as part of training.