Bitcoin implies decentralization, but aren't the actions of a mining pool that has the ability to influence the course of events in the BTC-network (returning the cost of inflated transaction fees to the sender. of course, considering that it was from "his own pocket".) some manifestation of "centralization"?
Neah, it's not centralization is just an individual making a decision.
Foundry can now reimburse that as it would be morally right or take the side of the miners and keep and share the fee, miners are also free to donate their share to the victim or leave the pool altogether if they think the decision is not right.
Mining in a pool is more like a commercial contract, it's nothing more really, mining pools gaining shares is more like a form of consensus, the true problem arises when we have just a few pools formed by a few mining farms or companies, but that's a different thing and another problem.
Ps, they don't influence the course of events, the fee was paid in a tx and if returned it will be in another tx, the event is set in stone.
The pool is usa based 0.7btc is over 40,000 usd. There are laws that do cover mistaken transactions.
The op very likely could win a judgement is his to her favor in a court of law.
The records are pretty clear. There was no need to send 0.7 btc in fees so it is pretty much a slam dunk that Foundry would lose if it went to court in the USA.
Of course the op may live in a different country which could make things more complicated.
Foundry would be pretty dumb not to answer the op as he can supposedly prove all of this.