no. many zen monks are indifferent about that. some what like "don't ask don't tell" even ven Seong Cheol in Korean Jogye order had not recognized that was true until in his 50s. his whole life was a succession of doubt, question to buddhist principles -karma, rebirth-. but eventually he accepted all of them through practice, contemplation and scholary study.
so you don't need to accept all of buddhist doctrenes as true. the discovery and acknowlegement of these doctrines are your own tasks just like the Buddha and other masters did. it's like in Asia, when lay people recieve five precepts, in some occasions, one can choose not to receive certain precepts. if one was a butcher, then he/she can choose not to receive the first precept. -ahimsa-