No, the Russians have access to all the OPCW information including the underlying lab reports from the Spiez labs.
They have correctly pointed out the Swiss lab's finding of BZ was left off the OPCW final report, as well as the fact the purity and concentration levels of the novichok-like agent the OPCW report refers to would have been more than fatal to anyone exposed.
Draw your own conclusions but the evidence points to a nonlethal BZ nerve agent being used, then a clumsy attempt by the British to doctor the samples with novichok.
There was more than one substance found, BZ being only one component, and Russia is selectively naming BZ? We need to see the full report and the complete analysis.