Quartzwood Crasher not triggering properly with Song-Mad Treachery [Fix in 4.7]

Planeswalker used: Koth of the hammer

I had one creature, an Akroan Sergeant, in play
The opponent had one creature Quartzwood Crasher
I used Koth's 2nd loyalty ability to give +6/+0, trample, and berserker (Rage of the Mountain)
So the Akroan Sergeant had trample
I used Song-mad Treachery to steal the Quartzwood Crasher.
The Akroan Sergeant attacked the opponent for 11 damage
The Quartzwood Crasher was triggered and created a 1/1 dinosaur token but did not give it +11/+11 per the Quartzwood Crasher text.
Then the Quartzwood Crasher appeared not to attack and was returned to the opponents control.
(The battle log showed that it did attack, but the opponent's HP was not reduced properly)

I should have ended the turn with a two 1/1 dinosaurs with +19/+19 (from both creature attacks) but only ended up with a single 1/1 dinosaur with no buff

You can see in the log where the opponent then took control of the Akroan sergeant from me and destroyed my 1/1 token.

Link to all battle log pictures: https://imgur.com/a/waDn1NM