Hello, i know this topic is old, but i was facing the same problem and i fix it
For using VCV-Rack as a master clock for the TD3
In the TD3 : Select USB as clock source and 24PPQ
In VCV : You need to send a clock multiplied by 24 to the CV-MIDI module from VCV and select the TD3 as a MIDI destination
I use Clocked from impromptu and it work just fine
I did not need to modifying the pulse width of clocked, i try but it make thing worst
Not related to the clock but useful though, i use the module shift pedal from Alikins to send a trigger to my modules’s reset; i also send it to FlipFLop from bogaudio then send the A to start and the B to stop (on the CV-MIDI).
Now when i press shift on my computer, it resting the clock, the sequencer AND the TD3, and restart it if i push it again