My thought is since you've put in the time and effort so far, scoop off the crud on the top the best you can and go ahead and press. Definitely add the K Meta in the pressed juice, add your yeast and nutrients, and see where it leads you. If you are fortunate, the infection is mainly on the top of your must and what is in the rest is minimal, hopefully to the point that Meta K will knock it out.
If you find that crud all through the must, maybe DON'T press , and just take the free-run juice.
You might want to clean and sanitize your equipment pretty good afterwards.
But you've went this far with the effort and work. A little more time and effort might not be a bad thing
Good luck