Tourist visas do not allow you to work as employed in the issuing country. But, they do not prohibit you from doing your 'home' work while on vacation.
So anyone from anywhere who is working on their laptop or smartphone while on short or long vacation is not under any penalty.
You can do your work/ personal stuff there, as long as your employment i.e. employer-employee relationship has no direct legal, financial bindings with the destination country of tourism.
PS: For all technical purposes, you are not going to work in the US, even if you are remotely working for your German employer. It is stupid for you to mention that. Why?
What is your intended relationship with US/ US Consulate/ US Visa - as a tourist.. right..?
Whether you go there and check your Germany work email or do some presentations remotely for your Germany company or take up a dance class for a few weekends, it is outside of the domain of your relationship with the US.