Still circumstantial and open to interpretation.

It could be narrative forcing but the writers have shown us enough that the dragons will still act on their own whims at times and are so far not 100% tamed. It was forced to retreat against a lot of spears before too, granted it's bigger now but so are the number of attackers and their weapons.

The arrival of the Masters fleet is an obvious set up for Yara and the Ironborn renegades to turn up and save the day when the dragon doesn't stick around to fight. Initially I thought it was her fleet hence the need to include huge slaver sigils on sails and an obligitory "It's the Master's" line.

"not only did he intentionally run her off the road to get her back to his bunker…"

'Pictures at an Exhibition' by Mussorgsky the music for Princess Carolyn’s painting fantasy :D Genius.