While I sympathize with your troubles, I do not want people who are looking for good information on the last chapter to be misled.
You, personally, may find it difficult to complete without spending money, but that does not make it impossible for all others. Collecting productions on the shortest interval (3 hrs), using MM enchantments, timers instants, portal profits, and other boosts, such as AWs, along with actively trading to get what you need when you need it, it is definitely possible, and not even that painful, to get through the last chapter without spending real world money. Not to mention that even if you need diamonds, there are quite a few good ways of obtaining them these days, such as Wishing Wells and Spire encounters.
Time, ah that precious resource. Time is what we must fork out in the last chapter. There are massive amounts of goods needed, and that takes some patience (or a lot of timer instants) to amass.
Farewell, CDM. May you find better enjoyments in your next game.