There is a difference between omni-benevolence and benevolence.
benevolence (countable and uncountable; plural benevolences)
1. (uncountable) disposition to do good
2. (uncountable) charitable kindness
3. (countable) an altruistic gift or act
Omni-benevolent
From Latin omni- meaning 'all', and benevolent, meaning 'good'. This may be a recent creation, extrapolating the contextual meanings of 'omniscient' and 'omnipotent' to describe, in a consistent manner, this third divine quality.
1. All-loving, or infinitely good, usually in reference to a deity or supernatural being, for example, 'god'. Its use is often with regards to the divine triad, whereby a deity is described to be simultaneously omniscient, omnipotent and omnibenevolent. This triad is used especially with the Christian god, Jehovah.
The omnibenevolent God, by definition, was unable to withhold forgiveness from his people.
As I see it, omni-benevolent means being unable to refuse help, unable to not do good things. An omni-benevolent being would be shackled by the need to do good things. And God doesn't like being shackled, by anything - he deliberately goes out of the way to avoid being stuck in a box or defined by us humans. He's benevolent, sure. (See my earlier quote. 1000 generations = ~20,000 years of blessing) But not omni-benevolent - and that's not necessarily a bad thing. Some things need to be punished. Actions have consequences, and we'd never learn from our mistakes if God just made the consequences 'go away'.