Syno breeding can be difficult and takes patience. Some species are easier to breed then others but it can be done. I haven't heard of anyone successfully breeding Njassae but Eupterus, Multipunctatious and Petricolas have certainly been bred in captivity. If you're planning on having a try would love to hear how it goes.
P.
Not planning on it yet was just wondering as i have a couple of wild caught and thought it would be nice to breed them in the future (running out of tanks with what i have already)