I'm not in R&D or anything so I don't want to try and say why but I can guarantee that no you cannot install the different components that make up a Managed node on different hosts at this time.
Feel free to post and idea in the ideas forum if you have a scenario you think this would be valuable though.
I can confirm as well from R&D point of view .- we don’t support that type of deployment. Mainly due to fact we don’t have control on these external services.
