Fix error in SalesForce Processbuilder process on installed app with guest user

We are receiving this error message on our third party installed package application in SalesForce when trying to hit it with a guest user in SalesForce (used for rest API integration + public visualforce page).

CANNOT_INSERT_UPDATE_ACTIVATE_ENTITY: SDOC.SDJobs: execution of BeforeInsert caused by: SDOC.SDUtil.SDException: No templates found when queried for SDJob with id of (null). Please confirm that the templates used for this job exist and the user has access. Class.SDOC.SDBatch.SDJobsTriggerHandler.setUsingFileMaster: line 2690, column 1 Class.SDOC.SDBatch.SDJobsTriggerHandler.initFileMaster: line 2647, column 1 Class.SDOC.SDBatch.SDJobsTriggerHandler.runTriggerHandler: line 2414, column 1 Trigger.SDOC.SDJobs: line 10, column 1. U kunt ExceptionCode-waarden opzoeken in de SOAP API Developer Guide.

What it's basically saying is;
- The template does not exist/ (maybe because of user not having acces to template ID)

Have tried the following things;
- Allowed acces to All installed S-docs objects
- Allowed acces to all Apex classes related to this object
- Update installed package to latest version

S-docs is saying error is not on their but on our side.