Yes, I've been to all of the major ones. Did you look at the map on my website homepage? I'm admittedly not sure which one you're referring to by immediately NW of Titus (since that's north of Titus and your title is asking about canyons south of Titus
) Did you mean immediately NW of Titanothere?
That's this one:
http://kaurijacobphotography.yolasite.co...2%20TR.pdf
NPS data calls it "Close-Call Canyon." Very nice but that major dry-fall is slick and it sounds like multiple groups have nearly had a nasty injury on it. The canyon before the dry-fall is nice, but it doesn't really get narrow until shortly before the dry-fall. Worth walking out there if you're curious, but it'll be a half-day hike at most.
The steep alluvial fan canyon is this one:
http://kaurijacobphotography.yolasite.co...wTitus.pdf
It's steep! But the views are good.
I'd HIGHLY recommend the canyon between Alluvial Canyon and Close Call Canyon. We did that one many years ago and I loved it. One of the first hikes I did with a digital camera as a teenager. Lots of good scrambling but nothing too challenging I recall, until you get to a beautiful amphitheater with a dry-fall that has to be hundreds of feet tall if I'm remembering correctly. And some nice narrows. I'd love to see someone do that hike and share photos of it. I remember it being a fun one, though if you're looking for something with little to no climbing it would not be a good fit. Could probably do this one in the morning then Close-Call Canyon in the afternoon.
Between Alluvial Canyon and Titus I remember getting stopped by a challenging dry-fall pretty quickly on in all of these. Looks like I don't have reports on two of them, must've not bothered to write anything up. They're kind of annoying in the sense that you get stopped so early on but the canyon beyond the impasse looks to have really nice narrows!
Link to my DV trip reports, and map of named places in DV (official and unofficial): http://kaurijacobphotography.yolasite.com