Fire Trap Spell

[Lord Cias]

There is a line in this spell's description that can be read two ways, and I'm trying to figure out what is intended.

If a fire trap is cast after a wizard lock, the former is negated, . . .

By "former" does it mean the first of the two spells mentioned in this line (fire trap) or the first of the two spells cast (wizard lock)?

[T. Foster]

The literal wording says the fire trap is negated, but I think the wizard lock being negated is what was intended (because that makes sense, and the other way around doesn't).

[Juju EyeBall]

I don't know, I think it makes sense to trap the door and then lock it.
A knock spell would unlock it unleashing the trap.

[darnizhaan]

I think the spirit of it is that the wizard lock is negated.