If options were exercised yesterday, shouldn't we know today?

Not really. There is often a time lag between the market capitalization summary report and the event and it appears that the source of the increase in the share count whether it is options or warrants is no longer recorded. 

Because DL is no longer an insider according to the NR his agent no longer has to report his trades.  In fact he could have traded before Dec 1 (the insider trade must be reported within 5 days of the trade) but if the subject ceases to be an insider within 5 days it is uncertain if we would see it reported.

And as TWG pointed out if POET is appointing a new director then they will need require options made available for that appointment.

This has not been mentioned yet but it would not surprise me if a new director is appointed who is associated with the Tier 1 or other significant customer/partner. 

All of  this is of course speculation.