I would say you are probably correct. A lot of it is semantics - I think prior to the eighties you’re just more likely to run into phrases like “adherent to Mao Zedong Thought” rather than “Marxist-Leninist-Maoist”.
Pol Pot and the Khmer Rouge's words on the matter
“Our two Parties, two governments and two peoples have maintained a fundamentally identical, correct, Marxist-Leninist stand.”
Speaking first, Hua Kuo-feng welcomed the Kampuchean comrades, calling their visit a “major event” in the relations between the two parties and countries. He said, “The Communist Party of Kampuchea, headed by comrade Pol Pot, is a staunch Marxist-Leninist Party.” He called the CPK “the force at the core leading the Kampuchean people in seizing victory in their revolution.”
In warmly praising Mao Tsetung Thought, Pol Pot said, “Following Marx, Engels, Lenin and Stalin, Chairman Mao and his thought have triumphantly stood the test of successive revolutionary storms.” He said that Mao Tsetung Thought today illuminates the path of revolution for people all over the world.
“More precisely,” Pol Pot said of Mao Tsetung Thought, “It is the most effective and sharp ideological and political weapon which infallibly guides our struggle to victory.”
emphasis mine
Undeniably, I would say, they were Maoist, but at the time ‘Maoism’ and ‘Marxism-Leninism’ were considered pretty much one and the same by “anti-revisionists” or those communists who split with the USSR after Khruschev’s coup d’etat. I’d say calling Pol Pot a ‘Maoist’ is a fair enough examination, it’s just that to him “Maoism” and “Marxism-Leninism” were synonymous. I’d maybe go so far as to call him a proto-MLM.
I would say you are probably correct. A lot of it is semantics - I think prior to the eighties you’re just more likely to run into phrases like “adherent to Mao Zedong Thought” rather than “Marxist-Leninist-Maoist”.
Pol Pot and the Khmer Rouge's words on the matter
emphasis mine
Undeniably, I would say, they were Maoist, but at the time ‘Maoism’ and ‘Marxism-Leninism’ were considered pretty much one and the same by “anti-revisionists” or those communists who split with the USSR after Khruschev’s coup d’etat. I’d say calling Pol Pot a ‘Maoist’ is a fair enough examination, it’s just that to him “Maoism” and “Marxism-Leninism” were synonymous. I’d maybe go so far as to call him a proto-MLM.
source: https://www.marxists.org/history/erol/ncm-3/cpml-pol-pot.htm