If we do not advertise, solicit, or promote this service of exchanging US dollars into Pesos in a Mexican bank, and if a sender who does not read, speak, or communicate the transaction in English to us, could we provide only the Spanish language disclosure to them since they will not be able to read or understand the English disclosure? What is the benefit of the English disclosure to him?

In the cases where the sender does not understand English, it appears the English disclosure only purpose is for examiners and auditors.

You're getting it. Other regulations, notably Regulation DD, indicate that disclosures may be in languages other than English as long as an English version is available. There is some cynicism involved in handing someone a detailed disclosure in a language he can't read, but the flip side of the coin is that most people you hand them to aren't going to read them regardless of what language they are in.

Requiring U.S. banks to provide disclosures in the customer's native language would be an overwhelming burden... Depending on who you ask, there are 4500 to 6500 different languages in the world.

No, you must always provide an English language disclosure. In addition, if you "advertise, solicit, or market remittance transfer services [in a foreign language], either orally, in writing, or electronically, at the office in which a sender conducts a transaction or asserts an error" (that phrase is further defined in the Commentary to 1005.31(g)), you have to provide disclosures in all such foreign languages, or in one of those languages that the Sender primarily used in conducting the purchase of the remittance transfer.

The law and the regulation don't suggest that the English disclosure will be of more help to the consumer than the foreign-language disclosure. Perhaps that's the way Congress tossed a bone to those who would like to establish English as the official language of the country. But the requirement is there, on a "because they said so" basis.

Since I have to provide the Disclosure in English and Spanish, can both English and Spanish be on one page? I am envising that the English in the left column, the Spanish in the Right Column and the variable data (senders name & address; Receivers name & address; date; amounts; fees; etc) in the middle column.

Yes, they may be on the same page.