When researching their publications the definition of the new covenant is very obscure and just to complicate things further is their idea that there are two covenants - Insight P 1126 " When mediating the new covenant Jesus made an additional covenant with his followers.. 'for a kingdom'."
They say this covenant is with the spiritual Israel of God and only the 144,000 belong to this. Because revelation talks about judging the Israel of God they say that as it is not the 'spiritual' Israel it means all of mankind.
They have closed the doors tof the Kingdom of God for the Great Crowd or 99.7% of their believers.