GAROUA-BOULAI, CAMEROON — Road transport has failed to fully resume between Cameroon and the landlocked Central African Republic after a top-level crisis meeting this week to reopen borders sealed by Cameroon following escalating violence in C.A.R. Hundreds of truck drivers say they will cross into C.A.R. when government troops protect them from rebels. Several hundred truck drivers who left Cameroon’s Douala seaport for Bangui, capital of the Central African Republic, say they are stranded in Garoua-Boulai, a town on Cameroon’s eastern border with C.A.R. C.A.R. is a conflict-ridden landlocked country that depends on the Douala seaport for about 95% of