IF your husband will have (permanent / long term) residency in Germany, he will be able to apply for a Thailand TR tourist visa through the eVisa system with the Thai consulates in Germany. For this to be applicable he would need to be "granted a residence visa [so any national visa, not a Schengen tourist visa] to stay [in Germany] for more than six months". Check the following websites section: "Am I eligible to apply online?"
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