Not true. The kicker reported it and that's the most reliable source in Germany you can find. In detail, they reported that the fee including add ons will "as far as it is humanly possible to judge reach 100m with a probability bordering certainty". They further more reported that the add ons are not reliant on titles by Chelsea. Also, The Athletic and co. reported that Havertz was NOT the most expensive transfer in Chelsea's history. Not regarding the initial fee and not after bonuses. This is false, plain and simple, as the statement by Chelsea itself proved.
So we have a very specific and detailed report by the most reliable German news paper that is in line with the reported sums since the beginning of the saga and then there are the sources that speak of a smaller fee which are also detailed but at least partially contain definitely false information. I don't even have a remainder of a doubt that the kicker article is correct