なくて済む/ないで済む => get by without doing ~ N2
を[経「へ」]て => After A N1
Time, Situation
~をたて(~を経て)      => through; after; via N1
ずに済む => get by without doing ~ N2
て済む => sufficient by; no problem to; resolve by ~ N3
~と(が)相まって => combining / together with… N1
Attached
に相違ない => without a doubt; certain; sure N2
に[相違「そうい」]ない => No doubt N2
Information, Report
と[相「あい」]まって => Along with A N1
Lists, examples