Are Latin causative verb ending -eō and Old Slavic -ити from verbs eō and ити ("to go")?
First, I wouldn't call Latin -eō verbs like caleō "be hot" and torpeō "be numb" causative; they're stative, expressing a state of being. The causatives would be calefaciō "make hot" and torpefaciō "make numb".
Second, the Latin ones at least aren't related to eō "go". The suffix comes from PIE *-éh₁-yeti, while the verb comes from *h₁ey- "go". I believe the Slavic suffix *-ěti and verb *jьti come from the same places as the Latin ones.