Lengua de vaca likely refers specifically to the shape of the leaf. The only lengua de vaca recorded in the ARS-GRIN database was collected by William A. Archer in 1935, from Leon, Guanajuato state and Enarnacion, Jalisco state in Mexico. These are practically the same place, about 80 miles NE of Guadalajara. One is in the seed collection, the other is no longer held.
"From Mexico. Seeds collected by W. A.
Archer, Bureau of Plant Industry. Received April 23, 1936.
-collected December 10, 1935, at Leon, Guanajuato. Cultivated tobacco.
114576. No. 3821. Lengua de vaoa
npgsweb.ars-grin.gov
-collected at Encarnacion, Jalisco, December 10, 1935. Cultivated tobacco.
114568. No. 3813. Lengua de Vaca NOT AVAILABLE AT GRIN"
There is nothing about lengua de vaca tobacco from Jamaica in the database. That proves nothing about the latter, but does make one curious.
Bob