However, my Blockchain.com Wallet is the only Wallet i could create these Addresses in
Are you certain you used the correct blockchain.com wallet? Do you have more than one?
How do you know the addresses you are checking on a blockchain explorer? Are they taken from the message you sent to the sender? Is there a chance you copied incorrect addresses or were victim to clipboard malware?
If you go to "Wallets & Addresses" on your blockchain.com wallet, can you find any of the segwit addresses in any of the wallets, including archived ones, under either used or unused addresses?