Ruined roggen? Fermentation temp question

Due to a screwup, my roggen(rye) fell to 54 degrees on day 2 of fermentation for about 24 hrs before I realized (WLP300 hefe yeast). I moved it to a warmer location and it's up to 68, but its already at 1.020, and the kreusen fell. Bubble activity is almost nil, and there is a bit of sulphur aroma.
Any hope for the aroma to clear? Think the yeast will keep going?
I was toying with the idea of boiling up 2liters of wheat extract and adding it along with another vial of yeast to try and get it going again.
Opinions welcome.

Roust it up and keep the temperature above 62. I bet it will pick back up again. I wouldn't worry about the sulfur this early, but of course the real question is how it tastes.