The empty site north of the Crossrail station at Canary Wharf will be built on. As part of that construction, a walkway will be created from the Canary Wharf Crossrail station to Poplar DLR station (which is nearer to the Crossrail station than the DLR station called Canary Wharf). Only about 250 metre walk, so no further than the walk if a Crossrail station had been built near LCY. Remember this section of Crossrail reuses the alignment of the former rail line, building in new tunnel to the LCY terminal has never been on the agenda.
In any case, the construction phase of Crossrail is complete - it's now all about systems/signalling fit out and integration - so this boat has long since sailed.