Russ, unless he suddenly catches fire for the next two years and produces playoff berths, won't be worth the value of the trade, nor will he be worth the value of the contract.
Essentially, it is how much sunk cost Denver wants to pursue.
The absolute most fascinating thing with Russ, especially now that this has happened across multiple coaches and multiple OCs, is how he can put up gaudy stats on paper and still preside over offenses that seem to struggle to gain yards outside of the "splash" plays. He is also very prone to at least one, maybe two, boneheaded plays a quarter.
This means that Russ will play well enough that the team will be only able to (outside of trades) reach for mid-level talent in the draft and hope they can develop them on the fly.
That said, cutting a mid-performing Russ means that the franchise will probably sink its season for the next few years. While Denver will be able to "rebuild" sooner, the question becomes just how much ownership is willing to bear in losses, both financial and on the field.