(3200) Phaeton is one of those asteroid-comet transition objects, so is particularly interesting. I see the article you refer to was the subject of a presentation by Teddy Kareta at the AAS Division of Planetary Sciences meeting last October. I have been corresponding with Teddy on another topic in recent months and am hoping to be a joint author on his latest paper.
Concerning Phaeton, Alex Pratt has recently drawn our attention to a successful occultation campaign to measure its shape. A couple of weeks ago the object underwent a stellar occultation as seen from the USA and we now know that its silhouette measures 5.7 x 4.7 km. See:
http://iota.jhuapl.edu/20190729PhaethonAug09.ppt
It is also on a target list of objects to be visited by the DESTINY+ space probe due to launch in 2022.