The first poem is not meant to critique at all, just a bit of fun.
I was doing some research on dactylic words and fantastic was on the list. I just took the word and played with it.
As you assume, to my ears and accent, the stress can be put on the first syllable.
To some extent, as Jess said earlier, you can read in a certain way, to stress the appropriate syllables. However, I completely agree with your parsing of it too, so I may have got it entirely wrong. Grins.
The second poem I included to see what Wesley thought. I actually find dactyl hard to write exclusively in. I thought my second poem had some dactyl feet, but wanted to see what our tutor thought.
One of the troubles is, I can't get 'Into the valley rode the six hundred................' out of my brain. Anything I write seems to be (poorly) echoing this.
Anyway, now Wesley has given us our brief, I shall go and do as he asked, so will have to get my thinking cap on and write my dactylic feet in Alexandrines..
For me, that will be tough. I'm not a Dum-da-da girl.
I will leave these two pieces up here though, even if I did jump the gun. They might be a point for discussion................ or not!
I do find it absolutely fascinating how regional accent, let alone international accent differences, can change a word so much.
Jx