I need a vault front handspring by next week ideally.
"I need X skill by Y date" is almost always the wrong mindset. Skills come when they come, and rushing them for a deadline will at best lead you to stress about it too much, and at worst will lead to poor and dangerous technique and injuries.
So my first and most important piece of advice is to relax, and recognize that you'll get it when you get it.
My second piece of advice is this: 99.9% of low- to mid-level vault problems occur in one of three places:
1) The run
All that's really important here is that your last three steps are at a full sprint. The rest of the run is just setup for that. So make sure you're accelerating throughout, and adjust your starting point as needed so you can keep your strides even at the end of the run. Lower body conditioning and running in general will help with this
2) The hurdle
Long, low, and fast. Think about pushing the board forward, like you're trying to make it slide under the table.
3) Your head
Let's be honest: approaching something as solid and immovable as a vault table at a full sprint is scary. And there isn't a surefire way to make it less scary, but one thing I've found can help is doing a front handspring or 3/4 front over something smaller (say, a spotting block), just to get used to it.