合う => do something together N3
~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
も同然 => just like; same as ~ N2
と同時に => at the same time as; while; simultaneously ~ N2
~もどうぜんだ(~も同然だ)      => just like; same as ~ N1
も[同然「どうぜん」]だ => The same as saying A, as good as A N2
Adjectival, Descriptions