Lecturer could see 1 report and not other - lodged within minutes of each other via desktop

[MlbSEV]

For 1 subject, I had 4 submission requirements (4 reports, submissions 1, 2, 3, & 4).

I uploaded 2 reports within minutes of each other - under submission 3 and 4, via CANVAS Apple Mac desktop.

CANVAS shows me the date/time of my submission.

My lecturer says he saw the one under submission 3, but not the one under submission 4, stating that ‘there must have been a difference between' his CANVAS view and mine. 

Could this happen? Where a lecturer could see 1 entry but not another for the same subject, for assessments uploaded from the desktop CANVAS version within minutes? He would have checked 12-24 hours after and reports there was nothing there.

Thanks, V