_N2914_.14.10.2.1 [concept.map.fct] paragraph 3 says,

Construct an expression E (as defined below) in the scope of the concept map.

This is the wrong context for this expression. Requirement members are visible to name lookup, and they are obviously not a desirable lookup result; names within the concept map should be invisible during the evaluation of E. Presumably this should read,

...in the scope in which the concept map is defined.