Using Blue Robotics Low LIght USB cameras in ROV system

I’m trying to use gstreamer to stream from the low-light USB webcam to QGroundControl with the following command:

gst-launch-1.0 -v v4l2src device=$DEVICE do-timestamp=true ! video/x-h264, width=$WIDTH, height=$HEIGHT, framerate=$FRAMERATE/1 ! h264parse ! queue ! rtph264pay config-interval=10 pt=96 ! udpsink host=192.168.1.222 port=5600

(already have WIDTH=1920, HEIGHT=1080, FRAMERATE=15, DEVICE=/dev/video1, with video1 verified to be the H.264 source)

It fails quickly with the following error:

ERROR: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Video device did not suggest any buffer size.
Additional debug info:
gstv4l2object.c(3417): gst_v4l2_object_decide_allocation (): /GstPipeline:pipeline0/GstV4l2Src:v4l2src0
Execution ended after 0:00:00.073182406

Using Raspbian Jessie on a Raspberry Pi 3 Model B.

(The older version of Raspbian is in play because I hope to install ROS Kinetic)

Any ideas on how to fix this?