Anyone in Germany has the assurance that there will be help and financial aid if anything goes seriously wrong with a vaccination. There is no need to additionally offer any payment. As it was said before, any kind of accommodation towards the anti vaxxers can be seen by them as admission of guilt.
"Oh, the government offers me payment if there's something wrong? That's the evidence, they would offer that if there wasn't something seriously wrong with the vaccine."
Anti vaxxers are not rational. You can't argue with an irrational person. They only acknowledge what they want to hear.