Why is the vibrator screws wont come out?

Ofek,

I think these screws have thread locker on them, so it will take a little extra coercing to get them to come out.

I'm not sure how you would've used a pentalobe screwdriver on a Phillips head, but maybe your screws head is different?

Try to find the correct head if it is NOT a Phillips screw.

If you've stripped the screw head already, your options are to grab the outside with some sort of pliers and turn it that way, slot the screws with a dremel and use a small flat blade screwdriver, or you have to drill the screws out. None of these methods are very nice or pretty and you have to be extremely careful so you don't damage any surrounding parts. Good luck and I hope this helps.