(Haven't you already asked this question on German SE: Pronunciation of consonants at a word-border? Please explain why you are re-asking it here.)
No, you don't get [dz]. The most commonly described accents of German don't have regressive voicing; instead, "lenis" obstruent consonants tend to be realized as voiceless whenever they are adjacent to a fortis obstruent.
The sound "/z/" is fairly often realized as voiceless [s] in all contexts; even in accents where it can be [z], that would be an unlikely realization after /t/ or /s/.
My description here, which is based on what I've read in linguistic sources, agrees with what mach said in the top-voted answer to your German SE question.