My Canon speedlites do not zoom with a zoom lens if they are pointed upwards to bounce, they go into manual zoom mode automatically. If the Yongnuo does not do this, you should set it manually (or find out if it's defective).
Agree with your likely cause, based on the images.
The YN622C, unlike Canon Wireless, allow both Auto-Zoom and Manual Zoom on remote flashes. The only time that Auto-zoom is useful is when the flash is on-camera, or on a stand alongside the shooter. For bounce, M/105mm or M/200mm will concentrate the spot on the ceiling or wall, reducing scatter and intensifying the light on the subject.
The bounce 50mm/70mm is enforced by the camera, depending on its 'adjust for sensor factor" setting.
If the background needs augmenting, add a couple of up-light flashes on stands.
PS - I would set the white balance differently, also.

