If you consider the timing too, it would have given Stalin alot of political clout against the allies.
“Oh Those rich guys are protecting Hitler, because he gave them his secrets!”
“Oh those evil capitalists are all on the same side anyways, Resist them or be a slave”
“Oh you better help me stay in power, and protect soviet interests, because look at how bad the Nazi’s are, and Hitler’s still around!”
It’s like Bin Laden. Sometimes it’s good to have a trump card you can drop and use, constantly, even if it militaryily or otherwise means nothing.