File DOIs from Dataverse are marked with "Dataset" in DataCite Fabrica, thus in the same way as dataset DOIs are; see this screenshot:

According to @pdurbin (cf. this post in the Dataverse Google Group),
"Dataset" is coming from at https://github.com/IQSS/dataverse/blob/v4.9.2/src/main/resources/edu/harvard/iq/dataverse/datacite_metadata_template.xml#L12 which is referenced from https://github.com/IQSS/dataverse/blob/v4.9.2/src/main/java/edu/harvard/iq/dataverse/DOIDataCiteRegisterService.java#L279 . As you can see, it's hard coded to "Dataset". You're saying that for files it should be something other that "Dataset", right? "File" or whatever. If so, can you please open a GitHub issue about this? We recently worked on this part of the code at #4795 for #4782 if you'd like to take a look."
I suggest that the metadata of files in Dataverse be changed, so that their DOIs show up not as "Dataset", but as "Dataset file" in DataCite Fabrica. I'm not sure which metadata field we should use for this. The DataCite metadata field resourceType resourceTypeGeneral is mandatory, and I guess it is the value of this field that is reflected in DataCite Fabrica. But according to the DataCite Metadata Schema 4.0, resourceTypeGeneral can only contain the following controlled list values:
Audiovisual
Collection
Dataset
Event
Image
InteractiveResource
Model
PhysicalObject
Service
Software
Sound
Text (15)
Workflow
Other
The list does not contain "Dataset file" or similar. So maybe we just have to specify the field ResourceType, which can contain any value. I suggest a general term like "File", which covers the parts of most types of datasets. Combined with resourceTypeGeneral, we then would get the following resource type description for dataset files:
Dataset/File
where Dataset = resourceTypeGeneral, and File = resourceType.
File DOIs from Dataverse are marked with "Dataset" in DataCite Fabrica, thus in the same way as dataset DOIs are; see this screenshot:
According to @pdurbin (cf. this post in the Dataverse Google Group),
I suggest that the metadata of files in Dataverse be changed, so that their DOIs show up not as "Dataset", but as "Dataset file" in DataCite Fabrica. I'm not sure which metadata field we should use for this. The DataCite metadata field resourceType resourceTypeGeneral is mandatory, and I guess it is the value of this field that is reflected in DataCite Fabrica. But according to the DataCite Metadata Schema 4.0, resourceTypeGeneral can only contain the following controlled list values:
Audiovisual
Collection
Dataset
Event
Image
InteractiveResource
Model
PhysicalObject
Service
Software
Sound
Text (15)
Workflow
Other
The list does not contain "Dataset file" or similar. So maybe we just have to specify the field ResourceType, which can contain any value. I suggest a general term like "File", which covers the parts of most types of datasets. Combined with resourceTypeGeneral, we then would get the following resource type description for dataset files:
Dataset/File
where Dataset = resourceTypeGeneral, and File = resourceType.