I think what he wants to do outside of the reordering is have his images open with a list of applied module …several of which are by default not active so he can decide for each image whether to turn them on. So point one this is not hard but for some reason he is getting weird results for this part. Secondly depending on the setting you have in DT preferences when you do this the active modules are in the active tab and the other ones will be in their home tabs as defined by your module groups ready to be activated but not all grouped together in one list. As @wpferguson mentioned you could do a second click on the active module tab but then you have also all the modules in DT many of which you have not used. However changing the setting I mentioned above to allow all modules in the history stack to appear in the active modules tab, at least in the couple of tests that I did addresses this as any module used in your stack active or otherwise can now be displayed in together in the active modules tab… These can be applied as a group by a style so what he wants it seems is or should be possible… I only did a couple of quick tests but it seemed to work for me and I also dragged a couple of modules and created duplicate instances and all that seemed to obey what was saved in the style when applied.
I think he could also do version of this with autopresets and populate the QA panel with these modules. So he could invoke a custom module preset for an a particular editing session. That could have his custom QA panel with all the modules added and then he could define auto presets for the modules he wanted so that by default they are applied active or inactive… then using QA the could enable and disable them as needed and perhaps even add a few key sliders… maybe …just thinking out loud…