Currently no Phoenix Eggs drop from killing mobs in the new Battleground Cathal Valley. This is inconsistent with other Battlegrounds and appears to be a bug.
Issue Timeline
6 May 2019 Tehrof created this issue
6 May 2019 Sherany triaged this issue
6 May 2019 Sherany changed the status of this issue from new to open
6 May 2019 Sherany assigned this issue from Nobody to Sherany
6 May 2019 Sherany changed the status of this issue from in_progress to resolved