Ah, I totally have missed this. Thank God I saved my test traffic to a file and I just found out that it was indeed detected by my two gateways and it stored the information in the metadata:
{"payload":"MTIzNDU=","port":1,"counter":11,"dev_eui":"0004A30B001AF385","metadata":[{"frequency":867.9,"datarate":"SF7BW125","codingrate":"4/5","gateway_timestamp":759087292,"gateway_time":"2016-05-05T12:18:42.531997202Z","channel":7,"server_time":"2016-05-05T12:18:42.432680879Z","rssi":-48,"lsnr":11.5,"rfchain":0,"crc":1,"modulation":"LORA","gateway_eui":"1DEE68C90BDE5305","altitude":8,"longitude":5.31575,"latitude":52.39776},{"frequency":867.9,"datarate":"SF7BW125","codingrate":"4/5","gateway_timestamp":1084325764,"gateway_time":"2016-05-05T12:18:42.561737666Z","channel":7,"server_time":"2016-05-05T12:18:42.441689472Z","rssi":-58,"lsnr":9.2,"rfchain":0,"crc":1,"modulation":"LORA","gateway_eui":"AA555A00080605A2","altitude":8,"longitude":5.31575,"latitude":52.39776}]}