That would explain why a Spanish spell-check did not catch it.

The story seems credible to me. The Spanish paper is unlikely source for Russian disinformation, and the story does not fit into the narratives pushed by Washington.

That does not mean that is necessarily true, but there should be an investigation into whether the US is putting bounties on Russian soldiers.

The story about alleged bounties on US soldiers in Afghanistan was a big deal during 2020. The Biden White House eventually admitted that there was no real evidence to support the story. What would be the US reaction have been a mercenary coming forward to say that a Russians were paying him to kill Americans?