Hi,
I've got the newest development version of Wireshark which has RTPS in its filter list. And RTPS is protocol is shown in associated ICMP messages, but not for the UDP messages. The DDS packets are simply fragmented UDP not having source and destination ports (the wire protocol?). In one of the menus for the dissector, it asks the TCP port, but we are using UDP.
Also, the UDP fragments are out of sequence. Is that normal/expected?