Babaoriley,
You stated:
it's difficult to believe they would leave themselves open to an end run, when all they had to do is get the darn 2nd tranche paid.
After rereading the NR my guess it would be a win/win for all parties.
POET negotiated a delay in the payment schedule from the Buyer, due in part to an unrelated third-party expressing interest in acquiring DenseLight in late December.
The unrelated third party continues to be in confidential discussions with all parties to participate in the current transaction.
Bold is mine