I caught this post and I wish I knew the for sure answer to your questions,
but here is my hunch:
I do know it is common in women with pco's to have much higher prolactin levels than estrogen and progesterone levels (the fat they store in the breasts) besides the fact you were a nursing mom.
You should get a hormone panel done to see how far off your estrogen and progesterone maybe compared to your androgen levels (these maybe free flowing in higher amounts: dhea,testosterone, estroidal conversion).
in other words, based on the info you posted, it sounds like you may have higher Lutenizing Hormone than Follicular Stimulating hormone.
Since its up to speculation on how exactly bovine ovarian glandulars affect the female system (other than knowing it stimulates the pituitary), its hard to be definite on whether or not it will be more beneficial to you versus the herbal route.
I think pumping promotes both cellular expansion and healthy prolactin levels, but since your prolactin levels seem to be higher than the other hormones, if you pump now, you maybe more likely to produce more milk eventhough it does not touch the nipple. Some have produced milk and even this is up in the air as it could have just been the combo of both BO/pumping since speculation is that it raises LH by pituitary stimulation (which in your case, you need the opposite effect).
I learned by my own experimentation of using mammary supplements for 4 months with phyto progestins and estrogens w/ daily pumping, I could not store fatty tissue in the breasts until I stopped them (and lowered my prolactin levels). It took a good couple of months.
I would suggest you take herbs to dry up the milk first so you can make room for fatty tissue storage.
If you have pco's you're most likely going to have to adress this issue(s) such as underlying glandular problems, blood sugar,diet, etc. first before anything that has to do with nbe or you are more likely to make things worse ( I am speaking from experience).
We are different than the average gal with a healthy functioning glandular system, so we have to work much harder and expect slower results because of it as it is a whole body system issue, but we can definitely get there, so never give up.
Good Luck, and research as much as you can...