Charles, please. The circuit you show has the 4067 supplied with 5V; this will not handle 0 - 10V signals! In fact, input voltages above 5.5V are likely to damage the device. This is clearly stated (albeit in Italian) on the page you got the link from, it would have been better if you had done likewise.

As you say, these devices are able to handle 0-10V signals, with the proper setup. This means a supply voltage (VDD) of at least 12V, which in turn means you will have to have a voltage translator between the MUX and your controller, because the Vih at 12V is about 9V.

Best regards,
Rob Klein.