scifi
That doesn't seem very likely, if the static port is rising, the instrument should indicate a positive rate of climb, even if the airplane's CofG is still going down.
The dip of the VSI during rotation is a known phenomenon arising from the change of airflow around the static port. I can't list which types get it and which don't but with the basic pressure instrument it's not as simple as 'the nose went up therefore a climb is indicated'.