Whole Wheat Breads Dough Conditioner

Good dough is not about being "conditioned". You can use that stuff to get the last 5% of perfection when you have already managed the first 95% with good process and ingredients, but it won't do magic.

In this case, you seem to expect whole wheat to act the same way as white flour. This is simply not possible. There is a large chemical difference between whole wheat flour and white flour, and they produce a very different type of dough. There is nothing you can add to make it otherwise.

If you are unhappy with the texture of your resulting bread, there are three things you can do. First, stop using 100% whole wheat flour. Mixing white and whole flour leads to simple, linearly predictive dough qualities. If you need a dough which is somewhat more like white flour dough, you can add some white flour until the result is good enough for you.

The second thing is to use recipes which are intended for whole wheat. It's not a simple substitute in white flour recipes, it usually needs much more water for a similar firmness, and can need longer proofing times.

The third one is to use a finely milled whole wheat flour. You say "freshly ground", so maybe you are milling at home. Many home mills leave the bran in rather large pieces, which cut up the gluten during kneading, leaving you with lackluster, flat bread. If you want good rise and soft bread, everything in the whole wheat flour, including the bran, should be very finely milled. Maybe try getting it through the food mill more than once. Sifting will also help, but then your flour won't be whole anymore. The third is to buy a better mill, but this is probably a huge investment. Maybe first try commercially milled fine whole wheat flour and only buy a better mill if it turns out that this is what has been missing for making your bread better suited to your taste.

Of the various things listed when looking up "dough conditioners" the only ones I'd think of using at home would be malted barley flour, lethicin and L-ascorbic acid (vitamin C.) An alternative for what the C is doing (oxidising) would be to buy your flour ahead and age it a few weeks for natural oxidising; possibly keeping it under refrigeration to reduce randicity, which can be an issue for whole wheat stored at room temperature or warmer.

That said, do I wonder if you are perhaps under-hydrating - whole wheat doughs tend to be obnoxiously sticky when "properly" hydrated - adding more flour to make them easy to work with is a common enough approach (been there, done that), with a common enough result that the end products are rock-hard...

My personal preference at this point is to have a more easily worked dough that is not 100% whole wheat. You can view "non-whole wheat flour" as a "dough conditioner" of sorts in that light, if you like.