When preventRemoteBuildQueue option is activated and the remote job never have been build, job failed with this error:
Got a blank response from Remote Jenkins Server, cannot continue.
In fact, you call an url /lastBuild on that job that return HTTP 404 because no build exists:
// get the ID of the Next Job to run.
if (this.getPreventRemoteBuildQueue()) {
listener.getLogger().println("Checking that the remote job " + jobName + " is not currently building.");
String preCheckUrlString = this.buildGetUrl(jobName, securityToken);
preCheckUrlString += "/lastBuild";
preCheckUrlString += "/api/json/";