I do not know of any Zimswitch enabled ATMs that let you deposit funds you can only withdraw, so no way of sending someone money using that technology. The Zimswitch webpage talks of ZIPIT as a cross bank payment mechanism, while the physical integration may be into the banks from ATM and POS there is still the need to integrate this at a software and business level so that the banks are happy to deposit money into a customer's account before they receive the funds themselves (from another bank which settles end of day). I think none of us appreciate the complexities of trying to get the banks to enable such functionality. Simply saying do it by ATM is not viable.
What would be nice is an indepth explanation from Zimswitch on how and where each bank is integrated, but I very much doubt they can make this info public.