The manufacturer might have been used a "replica substrate". Because in order to reduce the prices, they generally use replica substrates that are equivalent to original Rogers or any others.
If the specifications are tight, I recommend you to use original Rogers substrates.
In additional to, the sensitivity of a planar structure against manufacturing tolerances depends also on structure itself and manufacturing process. ( very thin lines, very close design, grounding etc.)
Do an Pareto analysis and find which part of your circuit is sensitive against tolerances.