So this has been sitting f o r e v e r, admittedly. I've been busy. :)
Houshmand and his boys have to get from Afghanistan back to the OE somehow. Originally I figured they'd break up into small groups of about 4 and trek over land through Persia more or less following old trading routes dating back to the silk road and before. This would allow them the opportunity to survey conditions in the Persian Empire, etc., but the more I think about it, the more this seems less likely, for a variety of geo-political, religious, and language related reasons.
So I wonder: how much boat/ship/whathaveyou traffic might there be across our Caspian Sea? Is this a more realistic route for our heros?
I've ruled out returning via Karachi-Jeddah, etc. for a variety of storyline reasons.
If I recall my research right - for a presentation in a Geography class, so it wasn't very detailed at all - the historical silk routes ran mostly through the plains north of Iran, a straight shot east-west from the south end of the Caspian to Samarkand.
Overland across the Caucasus from the Caspian Sea to the Black also looks quick practical from Wiki, so, by deduction, I'd expect that there'd be an active trade route along those lines. The hardest part would be north through the mountains to reach Samarkand in the first place.
In OTL I'd expect East-West cross-Caspian traffic to be close to zero. The Eastern coast is a desert, all the populationis on the South, West and North sides of the sea.
In N-verse - it's up to you.
Borys