I feel your pain, as the above thread was mine. And 44,000 miles later my front driveshaft centering bushing still has a hole drilled through it. For whatever it's worth, it doesn't cause any noticeable problems. I had actually forgotten about it. Now that I'm thinking about it again I'll probably notice a vibration.
I battled mine for ages, and heated it a lot. Of course it hit the point where if I heated it any more, i would most definitely destroy the bushing and then I'd be REALLY in trouble if I didn't get it out. I think it was a matter of not going past the point of salvagability.
For yours, I would try putting it in a vice, put the screwdriver or allen wrench through it, and then put a pry bar under the screwdriver/allen on each side of the bushing ... so you've got force pushing up on both sides of the bushing, using two pry bars. Heat it first for a bit. That's how I got one of mine out.
If that fails, you might just put it back on and see how it goes, unless the rubber is really damaged. I can't say it will work in every case, but in my case, the drilled hole did not render it noticeably dysfunctional. I put chassi grease in the holes though, to help keep moisture/gunk out. I should probably clean/regrease it and check the condition now that i think about it. Like I said, I'd managed to forget this traumatic episode.

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)