Hi,
sadly I got no response so far from the community and my efforts to get any kind of support from VMware were unsuccessful:
- regular support does not answer questions related to APIs
- TAP FAQ mentions support for partners, but a TAP representive informed me that the FAQ is wrong and you need to be TAP Elite level
- the recently introduced SDK support is so new that even sales needed several weeks to find out the conditions and pricing, which is BTW astronomic and in no relation to my problem
Basically, anyone who uses the API is walking on very thin ice. 
I would be happy about any hints!
Nikolaus