Such a nice guy! He helped me go through the method mentioned by TryNinja, it works but we needed to make some changes to the settings of the software.
If anyone has a similar issue with USDT stuck or lost because of sending it to a BTC wallet i would definitely recommend sending him a message.
Thanks thomasxyc for your kind words.
It's been a pleasure chatting with you and guiding you through the steps.
I'm glad we figured it all out !
It's a great thing, instead of wasting time waiting for @Yogg response (or PM him,) why not share the settings that worked with you, so that future members can get more details about the solution.
Next time you should be careful when sending, especially if the wallet was a platform or a closed source wallet.
Well, in this case it was an uncommon derivation method that was used by the BRD wallet.
The settings were in the "BIP32 tab",
"Client" : "MultiBit HD",
and "BIP32 derivation path" : "m/0'/0"
This is why Thomas' public address was not showing on the default page.
I believe this to be specific to this user's case and not a generic solution for everyone facing a similar issue.
I have also helped someone else who got mistakenly their USDT sent on the Binance Smart Chain as a BEP-20 Token.
With all these tokens, sidechains, tokens on sidechains, this is getting confusing.
Anyway, if someone is stuck in a similar situation, do not hesitate to
send me a PM.
I will never ask for your seed or your private key.(If someone does, this is not me but likely an impersonator.)