Typically no. There is no way to transfer information for any vendor PBX to any vendor PBX. Its a complete rebuild. If the Hicom has anyway to export information in their system to a CSV file, you might be able to manipulate the data into CUCM CSV templates for importing with Bulk Admin. By advise, rebuild. Gather the data you need which is basically First Name, Last name, extension, call forward settings. Those will be your majority of the user. The rest may have custom buttons, ring patterns, etc. (IE executives and assistatants, etc)