If room doesn't allow the use of the Member FDIC logo bug on advertising materials for deposit products, is it acceptable and compliant if only the words are used, "Member FDIC"?

Absolutely, as long as "Member FDIC" is still legible. The FDIC logo is never required on ads, although it can be used in place of the FDIC's "official advertising statement," which is "Member of the Federal Deposit Insurance Corporation," if you use the long version. "Member FDIC" is completely acceptable.

Thank you very much!