This particle alternates with lˀmr in OfA, thus showing that it is a colloquial shortening of the latter. See bibliography in DNWSI.
Some Syriac writers/translators, in quoting earlier writers, use the particle only in meaning 2 while citing direct citations without it, as in the cited example. The point being that the particle marks a different authorial point of view.
In poetry, the particle, normally "enclitic" after the first sense unit, can come elsewhere in the quote, when metrical considerations require it to be so, even at the very end of an extended quotation.