@melindagreen - I have to declare that the technical issues here are beyond my expertise. I reviewed the related documents and other related posts on nonce use. which make it seem like a lot of thise functionality is locked up internally in HubSpot.
I see some references to use of GTM as a workaround - for example in https://community.hubspot.com/t5/APIs-Integrations/Nonce-propagation-for-hubspot-chat-scripts/m-p/432076 which may offer a route forward. Otherwise an upvote on the idea community is all I may be able to offer.
Good luck!
Steve