I suspect it does to at least some degree. One of the key mechanisms is that these mappings turn a sequential memory task from free recall (e.g. what's the next digit again?) into cued recall (e.g. what was orange interacting with? oh yeah, it was in a shoe). I would be surprised if people with aphantasia don't benefit from the contextual reinstatement of a cue (i.e. even reinstating non-visual context).

(caveat emptor: I have a phd in cognitive psychology but am unfamiliar with aphantasia research).