This implies that paid Apple Developer accounts can sideload apps with the same BundleID as "official" App Store apps, but I still get an error when attempting to do so (with my personal paid account).
ERROR: Guru Meditation 0db732@892:3aea77 Failed: (9401) An App ID with Identifier '[REDACTED]' is not available. Please enter a different string.
This is using the local Anisette option. Additionally, trying to install with the "no Anisette" option (Anisette disabled) gives a 404 when providing my paid Developer accounts details.
ERROR: Guru Meditation 0db732@112:3aea77 Login failed: 404