Did you buy the ticket from United directly or via another source (real or online travel agent?)

Can you email yourself a new ETR&I from United.com? Since you're only seeing the correct segments online I'm wondering if you got the ETR&I while things were in transition (e.g. new segments had been confirmed but the cancellation for the old segments hadn't been fully processed).

united.com sometimes does weird with displaying segments that aren't in HK status (Holds Konfiirmed [sic]) status so it's possible (though I haven't seen it recently -- also haven't had a UA codeshare on NH ever) that the original flights are lingering in the PNR with a HX, IX , or OX status/action code ("Hold Cancel", "If Holding, Cancel", "Cancel only if requested segment available")