No you can only use content if you are able to comply with all the conditions of the license. Namely #4 which grants a right use a non-exclusive royalty free right to the content. In turn a person using the open content must also grant to the purchaser of their book the same right to use my open content and anything based on that open content. They not allowed to impose further restriction on my content.
So if they try to combine my Blackmarsh which was released under the OGL 1.0a license with a license using the proposed terms of OGL 1.1. Section 12 as they would not be able to fulfill clause #4 and other clause relating to the open content they are using.
Okay, I think I understand what you're saying here, but I don't believe that it works the way you're suggesting. Section 4 states that you're granted a "perpetual, worldwide, royalty-free, non-exclusive license with the exact terms of this License to Use, the Open Game Content." What that means is that you can use the OGL (specifically, v1.0 and v1.0a) without being charged royalties for it.
Now, presumably the OGL v1.1 won't have that particular clause, since WotC has said they want to charge royalties for publishers who earn more than $750,000 per year (presumably from OGL v1.1 materials that those publishers release). But that in no way violates the terms of the OGL v1.0 and v1.0a. You're not being charged royalties for using
those licenses, after all; you're being charged royalties for using v1.1. Even if they use the same material (since Section 9 permits Open Game Content published under one version of the OGL to be used with any other version of the OGL), that's a separate consideration; the same content can be subject to different licenses, after all, just like how a lot of old d20 products were subject to the OGL and the d20 STL.
EDIT: I'm still unclear where Section 12 fits into what you're saying, as it's specific to being restricted from using Open Game Content due to various governmental actions, which insofar as I'm aware aren't a factor in anything that's going on with the OGL v1.1, 1D&D, or WotC.