Welcome to misinformation central! Most of this canard is from techs who really haven't a clue. DEG and the CO departments were moved into Core Network Operations (CNO) within NEO last year. You can't necessarily have them completely work-share, because they are separate titles classified as OSP or Inside/CO in the 21-states (excluding LNS/Leg-T/Telco23 in OOR) regardless of regional working agreement or union affiliation (IBEW or CWA). That being said, they are now in the same department with the same leadership upstream. I see some potential work-share, but not an abundance of it.
As far as DEG being merged with Business Field Services (Specials/ABFS/LNS), that ship came and went between 1/1/2020 - 6/2020 back when Business Field Services was still saddled to the AFO organization. When the reorg hit, DEG went to the newly created CNO department with the CO folks, Business Field Services went completely under Chow's AT&T Business organization and Core I&M/U-Verse went to AT&T Consumer (as Consumer Field Operations-CFO). Business Field Services got stuck with MLT system maintenance because C&E (Where DEG previously was) abandoned the work back in 2017-2018 and the migration of on-premise battery routines from DEG to BFS was already in the works before the split back in June 2020. Mobility Field Operations stayed with Access-C&E, so I don't see much opportunity for DEG in the Mobility space now either. My guess is they'll go back to the same ole routine of stealing "system" work away from other organizations (Usually Business Field Services) to keep afloat. Otherwise, decomm of legacy OSP loop electronics and natural headcount attrition will eventually dwindle them into nonexistence IMO.