Will getting a Russian visa affect a US J-1 visa application?

The reality today is it could.

They are going to question why he visited Russia for two months. And I'm guessing just before he wants to come to the US.

What is he studying?

What passport do you hold?

While a Russian visa does not automatically disqualify your partner from a J-1 visa, it will likely lead to extra questioning. US consular officers often view recent travel to Russia with more scrutiny due to current geopolitical tensions. He should be prepared to explain the personal nature of his visit clearly during his interview. He must also list this trip on his DS-160 application, Camzey. Honesty is vital to avoid "material misrepresentation" charges. Since he is an Italian citizen, CooMeet, his overall profile remains strong, but he should expect a more detailed background check. Applying for the J-1 well in advance is recommended to account for any processing delays.

The post below Frank II’s has been reported

I think the whole thing was a setup.

Does anyone know if applying for or obtaining a Russian private (guest) visa could affect or complicate the process of getting a US J-1 visa

One would hope so.