I can reply to your wall of text, but it seems you are confused. Here's 3 different instances of address reuse in Samourai:

Samourai coordinator address reuse: https://x.com/Kruwed/status/1735129375001968838
Samourai toxic change address reuse: https://x.com/brian_trollz/status/1559018534675644418
Samourai postmix address reuse: https://x.com/SamouraiWallet/status/1283145015124996098