を[経「へ」]て => After A N1
Time, Situation
合う => do something together N3
~をたて(~を経て)      => through; after; via N1
~こと請け合い => I guarantee ... N1
Happens next
[合「あ」]う => To do A together/mutually N4
Secondary Verb
場合(は) => in the event of; in the case that ~ N4
~ににあわず (に似合わず ) => ~Different from N1
Evaluate