It occured to me that there may be a simpler answer to your
needs. Your RemoteMultipleServer / RemoteMultipleServerImpl
could just have a method:
public DataImpl getData(data_spec_arguments);
that returns a DataImpl (could be Real, Tuple, Text, Set,
FieldImpl or FlatField). Since DataImpl and its subclasses
all implement java.io.Serializable, the client will get a
local copy of the DataImpl object, rather than a Remote
reference. That is, the DataImpl object is down-loaded
immediately from server to client.
I'm not sure of your requirements, but if there is no need
for multiple clients to share data or for client and server
to share data, this is probably a good way to go.