They meddled when Obama was President, that's the only important thing here. The actual consequences of it or who were involved is obviously irrelevant.
He doesn't even understand (or is just counting on his supporters not to) that it would have been impossible for Obama to have intervened with the situation without causing a major constitutional crisis. Imagine the GOP reaction if he set about interfering with the election in any way shape or form because he suspected the Russians were up to something.
All he could do was leave it happen and set the wheels in motion on an investigation to find out exactly what went on.