From your other thread, your early entry trick is
Alternative Spell Source, which allows you to prepare Druid spells in Druid slots as Arcane spells.
I think between that and your PC having both Wizard and Druid levels you would be able to meet both the spirit and letter of the rules in creating Arcane scrolls from your Druid slots (albeit at a caster level cost but whatever).
AFAICT, the only restriction on creating Arcane or Divine scrolls comes from this line in the SRD:
The spell must be of the correct type (arcane or divine). Arcane spellcasters (wizards, sorcerers, and bards) can only use scrolls containing arcane spells, and divine spellcasters (clerics, druids, paladins, and rangers) can only use scrolls containing divine spells. (The type of scroll a character creates is also determined by his or her class.)
(bold added)
Since you have two classes the only restriction seems to not apply to you. That'd be the RAW argument.
From a spirit-of-the-rules argument: When you took Alternative Spell Source you turned Druid into a syzygy of Divine and Arcane casting. "Determined by your class" now means either, since your class can do both. (You also turned Wizard into a syzygy of Arcane and Divine casting, of course.)
Another spirit-of-the-rules argument might be that you can create Arcane scrolls from Druid slots after you take a level of Arcane Hierophant, since that's one class which advances both types of spellcasting. It's now "your class" in a significant way since you built for it and you intend to take all 10 levels, so once you have AH as "your class" then the restriction disappears in a poof of logic.
A third spirit-of-the-rules argument would be: If you were a Wizard with a Druid friend of the appropriate level, you could use your friend's spells to cooperatively create a magic item. Being your own friend shouldn't hinder the possibility of cooperation.
tl;dr - I can show you where the base game's rules stop applying to your PC, but only your DM can tell you what happens after that point.