As far as anyone here knows, are there any natural languages in which the apico-labial trill is a phoneme?
Sounds made using the tongue and lip/s are usually called "linguolabials" (eg in the IPA). There are a very few languages which make use of this sound as a phoneme, some examples are listed in the Wikipedia article on linguolabials. The article lists Coatlán Zapotec as having a linguolabial trill, but it appears to be iconic, used to represent a child's fart, not an actual phoneme.
There appear to be no reports of languages that use a linguolabial trill as a phoneme. Edward Vajda claims that the Chadic language Margi (spoken in Nigeria) has an "apico-labial flap", but this is not in agreement with other analyses of Margi (it may be that he meant to refer to the well-known labiodental flap of Margi).