I recommend reaching out to Netsuite OpenAir, they will need to provide you with the correct URL for connecting via Odata.
I was able to resolve the issue and connect to Odata. One of the articles on OpenAir customer forum mentioned that oData does not support SAML and LADPS users. So anyone trying to connect to OpenAir reports using OData will have to convert their SAML account to regular username password access and login into OpenAir.
Also in the OData connector in Tableau, you will have to put the entire URL for the report including the report name at the end.
For username, it has to be <Company_ID>\<OpenAir_username> and password (whatever shared by your OpenAir Admin).