I have recently come to the conclusion that the N1 に N2 construction (eg パンにバター）is more common than I thought. It is the only explanation I think of to make gramatical sense of the sentences below. Could somebody confirm I have this right (in bold) in the following case?
なお、本状と行き違いにお支払い済みの場合はお許しください Please ignore this notice if you have already paid (this card and your payment have crossed)
The following sentence has been removed as に should have been の：相手に言い分もわかったとはいえ、心から納得したわけではない ( "Although I understand were he's coming from, I can't really agree with him.")