Oi,
It seems that there's a bug regarding the Demonweb Pits Campaign rewards for reaching 600 progress; Take a look at the screenshots below.
Instead of the House Baenre set, the package incorrectly grants Netherese Engineer set, and unlocks purchasing it in the campaign store, alongside the Realm Engine Core artifact.
OR, the drops are intended, but the package description is wrong, which is quite sad, as the Netherese Engineer set is pretty much useless to me, and definitely not what I expected.

Comments
It is classified as tooltip text error.