By claiming Android compatibility, it's claiming to be the same platform when it isn't. The fact that even people like you, presumably a technically savvy IT insider, can't tell and are easily confused over that point is exactly why Google picked this fight.
My first instinct was to post here jokes about how Android is open, but in a closed way. I'm generally speaking an iOS/Apple symapathist. Just check my posting history. But on reflection and investigation fo what's actually going on, I think Google are trying to do the right thing. They have no leverage over Alibaba directly though, so they're putting pressure on Acer. If Acer wanted to fork Android like B&N or Amazon then fine, but getting the benefits of their OHA commitments means meeting their responsibilities. Supporting a marketing parasite like Alibaba is a step too far.
If you have emailed Aliyun and asked them to take it off then absolutely they are doing wrong leaving it on there. I haven't seen any information about what needs to be done to submit apps or if there is any review process (which should at least have caught the obvious Google apps).
If they don't remove it fairly promptly then yes maybe Google can take some action. I would expect that with clear cases of copyright infringement that Google at least could take a case.
In the mean time update your app to detect when it is running on Aliyun and include a half screen promotion for China's leading real Android phone.
So I have to keep searching if a Chinese company is pirating my apps? (How would I even know?).
They had the apps for a while and we knew about it only because google called them out.
How about you ask the guy who stole your car (After figuring out who stole it) and if they don't return it to you, then complain to police?
I don't know the Android platform but if your app logging shows massive numbers of devices that aren't matched by downloads reported by the Google store add some additional logging to try to work out why.
If the scale isn't large don't worry about it.
It is copyright infringement, you still have your car (going back to your analogy). Also it may be that Aliyun is the used car dealer that has stolen cars but don't know it, the pirates are the ones who uploaded/submitted it to them.
There have been cases on Apple and Google stores of copyright infringing apps although these get removed when reported.