Hi,
There is no option for now to have different workflows for the checkout for different user groups.
We're currently working on HikaShop, will will have a new checkout system which will be able to handle different workflows so it will be easier to do that.
For now, it would require modifying the views involved to auto submit themselves or skip the steps based on your criterias.
If you're a developer you can edit the files of the view "checkout" (for example, the "step" one is interesting as it controls the display of the views) via the menu Display>Views and add custom code to handle that.
Otherwise, I would recommend to contact a developer so that he can help you with that customization.
In that case, you could potentially contact our partners:
www.hikashop.com/home/our-partners.html