OSH has already stated that he sent the letter
here; so times up unfortunately.
As for your question, it really comes down to RAI. Clearly, the rules intended that the Shas'Ui be able to use both a Markerlight and a Pulse Rifle/Carbine, since you can only really use this if your Shas'Ui has a secondary weapon. This is really a useless upgrade since if you are using the Markerlight, one or two extra pulse shots isn't going to make much of a difference.