It’s pointless to talk to anyone until you get your summary statement.
You are absolutely forbidden from contacting the study section chair (or any other member of the study section) regarding your application. It is not impermissible to contact the SRO of the study section, but it is pointless, as they are only supposed to engage with you on issues relating to your application that arise prior to review.
Once your application has been reviewed, your PO becomes the point person for discussing the outcome of review. However, since your application was not discussed, the information available to the PO about review of your application is exactly the same as the information available to you: what is in the written critiques. If the PO has extensive experience with reviews by this study section and its members, then she *might* have some insights into how to interpret the reviews, but this is likely to be quite limited.
Your best resource for helping you interpret your written critiques is other PIs who have had grants reviewed, discussed, and scored by that study section, as well as any colleagues who are former/current members of the study section, but who did not serve the cycle in which your grant was reviewed. These individuals will be a source of information about the biases, preferences, etc, of the study section, and can help you read between the lines of your critiques to plan what to do next.
This whole process is very important, because what the critiques *say* were the key problems with your application aren’t necessarily what really sank it. If you can’t find anyone with direct knowledge of this study section, then your next best resource would be colleagues with extensive experience dealing with a broad array of study sections.
Don’t even think about appealing. And don’t bother trying to get that motherfucker Scarpa on the motherfucken phone.