There are apparently multiple versions of the Detox.
https://www.thegearpage.net/board/index.php?threads/detox-dupe.1985585/https://www.thegearpage.net/board/index.php?threads/help-with-detox-eq-pedal-need-only-one-photo.1436776/Between these two threads (and the schematic posted above) you'll see three different opamps.
NE5532, RC4558, RC4559, and OPA2134.
In one version you'll see that the cap across the volume pot appears to be 1nF, in another it isn't present at all, and here it is listed as 100nF.
In this photo you can see that the input pulldown resistor is 10M. (Brown Black Blue)
http://sia1.subirimagenes.net/img/2014/05/26/140526063817737345.jpgNot to mention a few obvious errors have been pointed out in the vero posted above, so until the OP posts an updated/corrected layout I wouldn't call it verified.
I'm just speculating without seeing the unit that was traced by the OP, but I've never seen a 47nF Vref filter cap on any pedal... The original that I've seen had a 4u7 tantalum. Looking at the pics in the threads above you'll see 4 tantalum capacitors, which suggests that is likely what they are using as well.
As far as the polarity protection, I will almost always use a series diode as opposed to parallel to ground..... A shorted protection diode is still a broken pedal to the average user.
As soon as I get some free time I'll draw up a schematic based on your trace of the Underdrive and we'll take a look.