Al-Andalus have a production of cotton since the middle-ages, but it was the Gossypium herbaceum, native of Arabia and Syria and suffers from the concurrence of Gossypium arboreum aka the indian cotton.
Indeed, the herbaceum delivers less fibers and with less quality (needing an harsher carding, removing an important part of cotton).
How Al-Andalus (most likely Grenada) could have beneficied of Indian cotton?
Maybe by trade, but it would need a direct one (by circosailing Africa, or by Islamic lands?) and critically the presence of a scholar able to see the differences of the two variants and decided to 1) take seeds, 2)maybe take indian peasants to learn their techniques 3)The support of the state.
For the consequences, if the acclimatation works, maybe Grenada could maintain a certain independece, being able to pay large tributes to Castille, and thanks to its trade of cotton in Europe and became anew a major place for mediterranean trade, not exclusive to cotton.
Of course, it would make Grenada an even more good target for annexion with a strong Castille, or in the absence of it, from an Aragon decided to keep control of mediterranean trade.