Restarting a stuck Wherry

[jmcc1889]

Hi again,

i posted in a previous link about my wherry sticking at 1018 i have tried gentle stirring but to now avail.
It was recommended that I introduce a dry beer enzyme and yeast vit.
I called at my local home brew store who stock Young's products and came away with a tub of Yeast nutrient and a tub of dried active yeast. They had no enzyme. (Excuse my ignorance if it is the same as what i bought)
The instructions on the Yeast nutrient and active yeast state to use 1 level teaspoon per gallon but i presume this is for new brews. What should I use with my existing brew?
They also had a 5g sachet of Re-start wine yeast, the label stated that it was for white or red wine suitable for all stuck fermintations below 8% ABV would this be suitable to use on my beer? The girl in the shop thought it would but confessed that she did'nt know a lot about home brew.

Thanks in advance!
John