@ monticm - I can confirm that can works on the G400. Another thing you can do is connect the two CAN channels on the G400 together using two CAN DWs and a cable. If you can get that setup to work, then something is wrong in your other hardware setup.
Please update this CAN bit timing for more accurate with 133MHz, this will be updated in next SDK.
var can1 = new ControllerAreaNetwork(ControllerAreaNetwork.Channel.One, new ControllerAreaNetwork.Timings(1, 7, 7, 55, 3)); // 125Kbs
var can1 = new ControllerAreaNetwork(ControllerAreaNetwork.Channel.One, new ControllerAreaNetwork.Timings(1, 4, 5, 37, 3)); // 250Kbs
var can1 = new ControllerAreaNetwork(ControllerAreaNetwork.Channel.One, new ControllerAreaNetwork.Timings(1, 1, 1, 37, 1)); // 500Kkbs
var can1 = new ControllerAreaNetwork(ControllerAreaNetwork.Channel.One, new ControllerAreaNetwork.Timings(1, 7, 7, 6, 3)); // 1000Kbs