yes, first get accrescent from the official github repo. 

most secure: use android developer apk signer to verify the accrescent signing certificate hash, then install appverifier from accrescent and use it to verify obtanium apk file. if it checks out, install obtanium, then use appverifier to verify all downloaded apks before installing and adding to obtanium (android verifies app update signatutes)

https://accrescent.app/faq#verifying 

less secure: install accrescent from github, install appverifier from accrescent. use appverifier to verify accrescent and obtanium apk. if it checks out, install obtanium. then use appverifier to verify all downloaded apks before installing and adding to obtanium (android verifies app update signatutes)