Hi,
Thanks for reaching out. With regards to your concern to set content exclusions for Campaigns, you could use CampaignCriterionService that manage campaign-level criteria. The CampaignCriterionService:get method will give you the details of content label exclusions set on campaigns based on the selector specified in the request. Please refer to this contentLabelType guide to know what all type of content label exclusions can be set through API. Let us know if you need additional information.
Regards,
Nikisha Patel, Google Ads API Team