Sorry the seed phrase was also found in the bag with the wallet and there is a possibility that you can transfer the coins to any other wallet. But morality can allow you to do that?
This is really one of the most difficult decisions to make. Let's be honest with ourselves. If a cleaner in a hotel room saw some huge amounts of money in a safe, how would she even know that what she saw was valuable? And how would Someone be working around with that kind of BTC on his or her hardware wallet attached with their passphrase on a piece of paper? The story isn't really that clear to me at all, and at some points it looks nearly impossible to me.
Another thing there is, we know taking what belongs to others is stealing no matter how it's obtained, but if the story is true, the possibility of the real owner of the wallet getting it back will really be small, as the cleaner might not have access to the hotel record where she could be able to get the contact details of the person, and going to the management with such information, there is no guarantee that if they take that hardware wallet they will give it to the right owner, as the amount in there is huge enough for a hotel receptionist to take as a payoff.
Yes, I get your point; it's nearly impossible, but not as if it's something that's impossible. The OP never mentioned that it's something that happened; it's just an imaginary story, apart from the part where he said a cleaner came across $70k.
But for the imaginary part of the story, it's possible that something like that can happen; mistakes do happen. Ok, just come to think of it, what if it was a client that came to the hotel for a business deal and right there in that hotel he received the 3 bitcoins? Right in his hotel room, the passphrase is just on the bed. Then he rushed to the toilet, and the cleaner stepped in. Seeing the wallet phrase and the hardware wallet, he (the cleaner) just took them and left. The question now is whether he will return the wallet or just stop his job and run away, because he (the client) will definitely find out that the clearner took it.
Let me tell you about a mistake I made in the past. I had a small diary that contained quite a lot of secret information about myself, my experiences in life, and my wallet phrases. So one day I went out to do something at a cyber cafe, and I brought along my diary. After my business was over in that cafe, I forgot that diary there, and when I got home, I had already spent some hours at home before I realised I had forgotten my diary at the cafe shop. I immediately logged into my mobile wallet, and my asset was still there. I just created a new wallet and moved my assets from the old wallet to the new one. The reason was because the pass phrase for the wallet that contained my funds was written inside the diary.
And my question is, what if someone had mistakenly read the diary and seen those phrases? Maybe I would have lost my asset. So, all I am saying is that mistakes do happen unexpectedly.