So Siemens are doing all this unpaid work in hope of Magnis getting up and running with the gigafactories so they can then get paid. Well it seems like Siemens knows a hell of a lot more than you.
Also if Siemens are paying all their people who are working on the machinery in NY as stated by Magnis these people would be getting paid by Siemens. This means Siemens are committing funds to the venture and your statement is flawed. In case you forgot the machinery belongs to the consortium which Magnis owns a large chunk of.