I think I'd initialize info.cacheable to true in this method so that if you call resolve outside of _resolveDataElementOptions then info contains a usable value. Then in _resolveDataElementOptions you can check if (info.cacheable && !custom) instead of if (info.cacheable)

It would have to be something like

if (info && info.cacheable === undefined) {
  info.cacheable = true;
}

because resolve is called in a loop. But I think its not needed. You'd need to provide the info object anyway, so not a biggie to provide initial value too.

In other words, I like to keep the initialization (and any related if's) out of loop

Maybe just document it then?

* @param {boolean} [info.cacheable] - Should be initialized to true. Will be updated by this method.