What is the correct APA citation style with two places and two publishers

From this APA library guide it says;

If more than one publisher is given, use the first one or the one that represents the home office, if given.

This answer at writer stackexchange supports this as well

So for your example the following should be fine for APA

Cazes, S., & Verick, S. (2013). The labour markets of emerging economies: Has growth translated into more and better jobs? Geneva: ILO.

I'm going to say something perhaps controversial here: I do not believe that location information is really relevant any more.

Consider, in your example, Palgrave Macmillan: Wikipedia tells me it is located in London, New York, Shanghai, Melbourne, Sydney, Hong Kong, Delhi, and Johannesburg. And what good does it do to know that? After all, anyone attempting to access the reference is going to use a library or the internet, rather than attempting to physically call some office in Melbourne to order a copy. My point is that I think you should fill in this obsolete slot with something reasonable (like you have done), but that I don't think it will actually matter to anybody.

It does seem reasonable to keep both imprints of publisher, and a hyphen like you've used (or maybe a slash) seem like reasonable enough ways of doing so.