The second tenuto mark is too far from the note head.- the gap should be no wider than a stave space.
I'm 100% sure it won't be that. First, because at the age at which pupils often take grade 2, their pencil and spacing controls are not finely-tuned enough to get these distances accurate - though I do make sure they understand that leger lines should be as near as possible to the same distance as stave lines, and definitely in alignment, so that the tune can still be clearly seen to be going up and down (I've seen faults in this area in professionally written violin parts, in G&S orchestra; the violinists just took it in their stride). They wouldn't penalise a child for not making stems an octave in length, for instance, and I doubt if they'd expect them to recognise a spacing fault as small as that in a printed copy when they still can't manage any better themselves.
But secondly, I've just tried to re-create that phrase on Sibelius, and without the tie, the tenuto was where you said it should be - but as soon as I added the tie, it shifted down to more or less where we see it on the paper. So the tie displaces the tenuto.
It has to be the second tenuto sign - give the note its full length but don't slur it to the next - how can you have two tied notes and one of them is not joined to the other?