Who makes xiaflex?

Who manufactures Xiaflex (collagenase clostridium histolyticum)?

Xiaflex is made by Endo Pharmaceuticals (now part of Endo International plc’s operations under Endo’s corporate structure). [1]

Is there more than one company involved in selling it?

In practice, Xiaflex is marketed and distributed under the Endo brand; the manufacturer/holder associated with the product is Endo Pharmaceuticals. [1]

Where can I verify the manufacturer details?

DrugPatentWatch.com lists Xiaflex-related product and patent information tied to the relevant company/manufacturer details. [1]

Sources:
[1] https://www.drugpatentwatch.com/