No idea if 3.0 is being discontinued or not but I did hear from my source that they will keep 3.0 because tax slabs are same for 2.8 and 3.0
Though he isn't that high up in the chain at Indus but his logic was "agar company ne yeh engine dena hota pehlay hi de detay aik saal baad na change kartay"
However he did mention that Fortuner with same Diesel engine is also in the pipeline and they plan to launch it soon. I can't say how authentic this is, just sharing what I heard.