In Job 1:15, we read that the Sabeans fell upon and took Job's cattle and she-asses. Then they killed the young men, or servants, of Job, by the sword. Only one of these servants got away, and it is he who is telling Job these things.
וָאִמָּלְטָה רַק-אֲנִי לְבַדִּי לְהַגִּיד לָךְ
Apparently, וָאִמָּלְטָה is cohortative. In Joüon & Muraoka's A Grammar of Biblical Hebrew (2nd Ed.), pg. 127 it says that the cohortative is the "volitive mood of the first person. It has a direct use (e.g. May I kill!, I wish/want to kill!) and an indirect or subordinated use (with ו), (e.g. in order that I may kill)".
The grammar indicates that one discerns the difference b/t the direct/indirect depending on how the prefixed ו is used, which seems somewhat subjective.
On pg. 346 it says about the indirect volitive, “the volitive nuance is often very weak and does not always need to be translated." It goes on to say that it can indicate purpose under certain circumstances. It seems to me, however, that this is not an indirect volitive, from the context.
It seems quite unclear generally how וָאִמָּלְטָה should be understood and translated.
"And they struck the servants by the sword, and I wanted to escape, only I alone, to tell you."?
This doesn't seem right, given that we have a Niphal for the verb. Another alternative is "...and [they] wanted me to escape, only I alone, to tell you." So the idea is that the Sabeans wanted to kill everyone but leave one to relate what happened to Job.
Both of these seem quite different from standard translations I have seen, which render the verb as a simple past "I, only I, escaped to tell you."