I checked your link but I get a " You should use the redeem script, not its address!" message - but didn't really check how this works, maybe I should readthe documentation first, will do so tomorrow.
Ahh right, sure.
You'll want to go back to the mempool.space page for the transaction you sent me, click on "Details" again, and copy and paste the text after where it says "OP_PUSHBYTES_37" for each address. There's one of those for each address. The string will start with "5121" and will be 74 characters long.
If you paste that string in to coinb.in and hit load, it will find the address.