New joint DHT11/DHT22 module

You can't just replace the pinMode(ht.pin,'input_pullup'); with a digitalPulse (which it seems you've done). It'll mean the DHT22 is fighting against the Espruino board to pull the signal line low and something might get damaged.

As far as I can tell, the marker isn't fired late. It should immediately set the pin low, then set it to 'input_pullup' after 1ms. It then waits 5ms for the response.

My guess is that on ESP8266, it often messes up the timing (maybe WiFi needs to process something for a few ms) and executes the pinMode and the other timeout right after each other, so there is no time for the result to appear.

I guess you could work around this by just nesting the timeouts?

  setTimeout(function() {pinMode(ht.pin,'input_pullup');},1);
  setTimeout(function() {

to:

  setTimeout(function() {
    pinMode(ht.pin,'input_pullup');
    setTimeout(function() {
    // ...
    }, 6);
  },1);