but they themselves implement it so you can use oauth 2 as an authentication method to connect to netsuite

i think i get what you mean, but going back i guess, from me it's not apparent there is a method to do the fb oauth2 handshake kind of authentication - i.e from NS to FB request header, then request reply from FB to NS with bearer token then for NS to reply with the bearer token to finish the handshake I dont think this level of API endpoint response is possible with restlet?

those handshakes are browser based, use a tool that supports oauth 2. The access tokens you as and the end are basically equivalent to basic authentication