To me it looked close enough just because of its size compared to the King. If the frog had been larger this may have ended much more quickly for the mouse saving both it and the frog some pain.
It is always a thrill to see a live mouse get devoured by a large frog, but we must think of the well being of the frog and be prepared to jump in when something goes wrong.
I'm glad you learned your lesson.
Thank you
Jerrod