Can Buddha Damma be reduced to Paticca Samuppada? Can the teaching be reduced to Paticca Samuppada? Has lord Buddha preached so in any Sutta? During vipassana meditation, the practitioner focuses on impermanence, dissatisfaction and non-self. After this, when getting Arhantship, is it Paticca Samuppada that is understood by the disciple?
The Buddha's Dharma is beautiful in the beginning, beautiful in the middle, and beautiful in the end. Absent need for addition or reduction. It would be overly simplistic to reduce the entire teaching to one doctrinal aspect - even if it were dependent origination. 

Having said that - one who sees dependent origination, sees the Dharma. One who sees the Dharma sees dependent origination. Without realizing the knowledge behind paticcasamuppada, it would not be possible progress to sainthood. For even Sotapannas need to see the Dharma in order to eradicate the first three fetters.

Rather than postulating what it is that an arahant realizes at the point of fruition that successfully eradicates the asavas, focus more on the cultivation of morality and concentration. This will arm you with the tools you need to investigate phenomenons for yourself. As your paramitas mature, you will realize these truths progressively.