mxtoolbox indicates that SPF for telus.com redirects to "_spf_telus_com.nssi.telus.com", which designates "_spf.google.com" as an authorized sender. That's why

mxtoolbox indicates that SPF for telus.com redirects to "_spf_telus_com.nssi.telus.com", which designates "_spf.google.com" as an authorized sender. That's why the SPF check doesn't fail. However, in the year 2018 I'm shocked that Gmail would put messages that fail dmarc into users' inboxes.