so with the retail mode watches i've had to just flash watch firmware onto them using net odin (similar to normal odin, just over wifi). i havent done this on the newest watches but was able to on older watches. there are guides on how to flash watches using net odin online. probably differ by model so im gonna let you google exactly what you need.
I dont think those passwords will work on watches. and honestly, in prob 10 years of removing FRPs and retail modes that 5444, M729Q16K8546 combo has never actually worked for me, even though it's always the first answer I see.