Airline Carry On Rules

I am asking since my crony is “stuck” in Montevideo, Uruguay. He is a Mexican immigrant, though He flew to Uruguay from the United States. He was told which he can usually stay in Uruguay for 90 days. He was starting to go to Mexico a couple of days after the 90 days which was schedule. However, there was a business which his babies, who live in Uruguay, were ill the night prior to he left. He had to cancel, and haven an additional day which was roughly a month later. He was ready to go, though he was stopped at the check-in since a workman there told him he had to compensate 100 USD for a carry-on bag. He saw the worker put his income in his pocket, and demanded to give behind his hundred. He was told which he could not leave, and so once more, he cancelled his ticket. The subsequent day, he went behind to speak to American Airlines bureau and told them what happened. He was told he can still leave and does not have to compensate additional for his bags, though has to compensate for immigration. He had to compensate the immigration be