"...Iains, a convicted criminal and one of two others telling us the opposite."

Good English, perfectly clear in its meaning (bar the typo "of", barely noticeable in the flow of the sentence). Perhaps you thought he meant "Iains (a convicted criminal) and one or two others telling us the opposite" or "Iains, a convicted criminal, and one or two others telling us the opposite." I recommend a strong coffee and the donning of reading glasses, along with resort to a tome on English grammar and punctuation!