shipment is in clearance in Cologne for 5 weeks

[Itoero]

It has finally arrived! The package was opened up.

If they checked the product and cleared it, does that mean it's real idebenone?

When they found it's not idebenone then they could not know what it really is in which case they would not clear it.

Does this makes sense?

[CharonY]

It is unlikely that they went through the trouble to make a detailed analysis. More likely that (if anything) they ran some standard testing for contraband.