Did you try
nm -D libflame.so | grep dnrm2_
?
Given that it is provided by libblis (these are 64 bit integers, hence the extra 64 suffix):
> nm -D ~/.julia/artifacts/3d9c1a6f0bd9ed317a031702dc47068a05ac7a9c/lib/libblis.so | grep dnrm2 (base)
0000000000a798b0 T cblas_dnrm2
0000000000a6b630 T dnrm2_64_
0000000000a740a0 T dnrm2sub_64_
I’m guessing it isn’t provided by libflame, and instead that it expects you to (dynamically?) link libblis.
Related: Calling code from a library (.so): works on one system, fails on another - #3 by m-j-w