i am going to respect my friend's work product and not release any of his list at this time and have indicated to him that there a folks wishing to have his list.
however, some of your questions i think i can answer.
Q: which JAV idols made bestiality videos? A: javlibrary+com has listed a fair number of jav beast videos (no covers are provided) and if you determine the product id (e.g., KRFV-001 to KRFV-029 by karma, DFE-008 (risa murakami) by fearless, DJK-001 to DJK-040 by gekiko, MAD-03 to MAD-84 by glory quest, MAXD-03 to MAXD-22 by alpha international, KMD-01 to KMD-04 by TTS, GLSE-001 tp GLSE-025 by global secret) you can determine most of the actress names listed at javlibrary (especially at the japanese title of the video ~ the japanese title often has the name of the actress in the title).
here is a list of the glory quest animal emperor /
獣皇 videos: https://ja.wikipedia.org/wiki/獣皇 with a list of the actresses in japanese
and, of course, the first "dog game" video (MAXD-04) the actress was the magnificent sakurada sakura
Q: have new bestiality videos been made? A: by my discernment (admittedly greatly based on my friend's excel as well as my own collection of jav beast video) there have been no new jav beast videos made in at least 5 years and probably for an even longer period of time.
my Q: why aren't more japanese beast video being produced?
my A: i haven't been able to determine this issue to my full satisfaction, although i think i have come up with a possible answer. in the late 2000s japan strengthened its animal welfare laws. however, more likely the reduction of jav beast production is related to the backlash caused by the gang rapes and rape convictions associated with Bakky Visual Planning. i believe because of the Bakky Visual Planning criminal convictions and increased complaints by actreasses and consumer organizations (Consumer Involvement in Japanese Pornography Production @
https://digitalcommons.uri.edu/cgi/viewcontent.cgi?article=1106&context=dignity) all japanese video that portrays non-consentual activity is under increased scrutiny. if producers of video think they might be prosecuted for making a video portraying non-consenual activity (see, e.g., Japan: Coerced filming of Adult Pornographic videos @
http://hrn.or.jp/eng/wp-content/upl...AVindustry-20160303-tentative-translation.pdf), including bestiality. the producers have prudently stopped making videos. and i am sure the diminution of the production of most western beast video has had an effect on the japanese market for such video as well.