This type of situation is dependent on the integration and it's recommended to discuss with offering management the specifics to make sure you have sufficient coverage in an audit. There's only a handful of people that are able to officially state whether something is allowed or not allowed under our licensing.
Some integrations will not require any licenses. For example, if you perform purchasing in an external system (such as JDE) and are replicating that data into Maximo, a license is not required. Activities covered under self-service licensing such as creating a service request also do not require a license.
On the other side, some integrations such as a mobile application to manage work orders cannot be covered under a single named license if the activities are performed by multiple users. If 5 people are entering work order details in a mobile application, all 5 of those users need a license. They can't be covered by a single named user simply because a single API key is used.