Hiya @mit and thanks for the thoughtful question! This is not a recommended configuration; please see [Support Guide] Why not proxy to Netlify? for many more details about why (and about how we do not provide tech support for this configuration, though we clearly cannot stop you from doing it).
What I can tell you despite that is that Netlify only serves files via its CDN; there is no “direct to origin” setting (CDN nodes will fetch from the origin; their proxy will connect to the nearest CDN node, network-wise automatically; there are usually several CDN nodes in any location, so they’ll likely connect to various servers with their various requests). We also do rate limit for many rapid connections to the same domain from the same IP so hopefully you won’t have much traffic, or hopefully instead their proxy consists of a large pool of nodes and traffic comes from all of them spread out, which would be less likely to trigger our automatic blocks.
Note that we do provide limited tech support for this configuration (have several customers using akamai as a CDN fronting our service) at the Enterprise account level.
We can also ensure that these blocks won’t occur, on our Enterprise plan. Let me know if you’d like to talk with our Sales team about what that could look like, if it seems like it might suit your business needs.