I don't know if anyone else will chime in, so thank you Cassius . It's so sad that the extent fragments, the letters, and Lucretius are all we have to resolve the issue of how he could believe in gods that neither he or anyone had ever sensed with the five senses, nor could know by prolepsis since no one had ever sensed them by experience.
But since he was acclaimed for speaking frankly, when he says there are gods, to me, he believes they exist without evidence.
If he is being inconsistent in his methodology of discovering the reality of the gods, it does not weaken his reasoning and his reasons to teach careful pleasure is easy and pain is fleeting and avoidable. Those being true, Happiness is achievable. In a way, the apparent inconsistency of methodology illuminates Epicurus' common humanity.
P.S. So, to recap my thoughts underlying the subject here: Epicurus says nothing comes from nothing; atoms are eternal building blocks of all other matter; the soul and the body are one material being; the gods are corporal. So, he thinks they are composed of matter; and they exist blessedly.
Yet, still scratching my head: Under this, his gods being immortal are coexistent with eternal atoms, even though the gods are composed of atoms?