Question about Flamethrower Team Assistant weapons

Hey, i’m very new to K47 (or Bolt Action) mostly just building a small German force for it and I was just wondering if there’s any particular reason why the assistant in the Flamethrower team only has a pistol (and has no ability to upgrade to a rifle)?

Just seems like a strange design choice, as every single model kit of a Flamethrower weapons team sold (that i’m aware of) has the assistant armed with a rifle and if you run a Volksgrenadier squad as Engineers and equip a Flamethrower, this guys’ assistant would be equipped with the default rifle (unless i’m missing some extra rule about it?)

I’m just thinking that maybe it might be an error in the army list, because the assistant in the 2-man Sniper team is able to upgrade its pistol to a rifle, or do you think it’s more of a balance thing? Even if it seems to me that an Engineer squad with the Flamethrower is a much better way to run Flamethrowers (if my math is correct, it even becomes cheaper points-per-model wise)