Before Away Teams became a thing there we had people "loaned" to teams to update our code for team projects. I remember during one of the code reviews I did for someone "loaned" to us involved him commenting out validation checks in critical systems that had legal and financial ramifications. When I asked him why he commented it out he said "Oh, my code didn't work with those checks in there so I removed them." I get that the code is complex and he doesn't have the full domain knowledge, but he didn't even ask why they were there and why certain use cases were not allowed for that part of the code.
This model only works if the away teams are the most competent people you have. Generally the “loaning” business is a cowardly way for teams to trade the worst engineers you have (bonus point if that engineer is someone who everyone praises but is secretly shit and only the manager knows that reality).
I don't see how having Away Teams fixes this issue. The Away Team member is still free to write shitty code (or un-write good code, as in this case), and it is still the responsibility of the home team to catch that in code reviews.
