IADD / Gibson Reports holds a copy of the ERD database that can be found at:https://public.tableau.com/views/IADDERDDatabase5-1-19/FrontPage?:display_count=y&:origin=viz_share_link&:showVizHome=no
while this doesn't specifically include 8-1/2" section lengths, it would be worth asking your JV Partners as ExxonMobil have significant presence in the longest stepout wells in Sakhalin. Though from memory the 8-1/2" sections aren't the longest due to the well design.
Probably the closest analogous well where a 8-1/2" section length has been publicised would be BD-04A by Maersk Qatar in the Al Shaheen field with a reported departure of 37,956 ft, MD of 40,320 ft, 9-5/8" shoe at 4,871 ft, and 8-1/2" section length of 35,449 ft (see: https://www.drillingcontractor.org/continuous-improvements-lead-to-maersk-oil-qatars-longest-horizontal-well-in-the-world-1924