From another thread (Trautloft´s air victories in Spain) this detail:
September the 1st , J. Fernandez R., the Garcia Lacalle wingman was shooted down on a NiD 52 but, against Fiats. Might be, an identification mistake...
From my limited sources I could not find any claims of Italian Fiat CR 32 pilots during the days of 1.-3.9.1936 - it seems that they claimed nothing on those days (?). Misidentifying He 51 as Fiat CR 32 may well have happened by the Republican side.
About Heilman/Hantz I can tell nothing - German/Austrian/Swiss volunteer or something else? From the list of pilots of FARE (Air Force of Spanish Republic) I found this person:
Hillman, Edward - pilot of 2nd escadrille (?) "Lafaytte", entered to service in 1936.
Source:
http://www.sbhac.net/Republica/Fuerz...a/Personal.htm
Could "Heilman" be actually Hillman?