I might be missing something but it looks to me that there is a very simple solution to your problem. Rename the controller from "plugin_wiki" to "pretty_url". Then use the following routes.py:
routers = dict(
app1 = dict(
domain = "domain1.com",
default_controller = "default",
default_function = "myfunc1"
),
app2 = dict(
domain = "domain2.com",
default_controller = "default",
default_function = "myfunc2"
)
)

