Just for reference here is the full Defence Line rule:

If an enemy unit is within 1" of this terrain feature, you can still make a charge move against it so long as the charging unit ends its charge move touching that terrain feature and within 2" of the target unit. Units are eligible to fight, and models can make attacks with melee weapons, if their target is on the opposite side of this terrain feature and within 2".

And charges effectively work as: roll 2d6 if that is enough to get in engagement range the charge is successful and then you actually make your charge move.

So you check if your 2d6 is enough to get in engagement range

if so you can make your charge move

which can end not in engagement range, but touching the terrain and within 2" of an enemy.

It's honestly a tricky interaction, but rules as written I've got to go with no. Rules as intended I could easily see it being a yes. It might need an faq.