Originally Posted by Moriens

No comment on the discrimination issues, but is it possible that a gate agent might gate-check a carry-on due to a full SAT-IAH flight, so the carry-on is available to be picked up at the gate in IAH, but a passenger might reasonably interpret “we'll check your bag” as checking it through (interline to HYD in this case)?

Then there might be a forlorn bag sitting at a gate in IAH until someone figures out where it belongs, which could explain the four-day delay for that bag.