This is not a problem of an unsupported trunk or template. This display has always only shown the text which has entered the name in the incoming rule.
So, a problem that the V20 has, because you can no longer do this.
At the moment I would use the V20 with caution, as there are still problems that have not been solved. There are many small problems but in total you need a lot of creative ideas to solve them as a technician.
Currently I would use the V18 until the V20 achieves the same quality. If the V20 is a must, first set up the V18 and set up the configuration completely and then migrate to V20 and set up the additional configurations such as the departments.