Deloitte settled HPE's Autonomy lawsuit for $45m back in 2016 and agreed to cooperate with US DoJ

So that's why they're not named alongside Lynch and Hussain

Exclusive  Hewlett Packard Enterprise settled its potential lawsuit against Autonomy auditors Deloitte for $45m in 2016, The Register can reveal – shedding new light on how the $5bn lawsuit against former Autonomy CEO Mike Lynch and ex-CFO Sushovan Hussain came about.…

from The Register