She does not come on Saturday??
report it (although this being the future unit they probably want people to focus on the future tense)
So without context this could either be present tense for future?
It's the present tense grammatically, but it can be used to mean a future action, too, so yes. Just think of the unit about time: there were a lot of sentences just like this one translated in the present tense.
'På' in Danish is used for future. If it was present tense (like a recurring thing that she does not come on Saturday) it would be 'om'
Why not 'She will not come on Saturday"