We declare dependencies on the installation of the executables we need for MSI construction here:

https://github.com/mongodb/mongo/blob/c1e603921ceba1c55d32b7978323cdc3261c7192/src/mongo/installer/msi/SConscript#L168-L181

But we don't declare dependencies on the PDB installation. That can allow MSI construction to happen before SCons has copied the PDBs into the install directory.

We should declare dependencies on the PDBs as well, or consider changing the explicit dependencies to declare a dependency on a hygienic builds install alias.