The idea that Democratic politicos may not be honorable is a defensible hypothesis and debatable proposition on its own merit. The problem here is the timing and context of the criticism.
If the criticism occurs as a response to clear and obvious Democrat malfeasance, then OK, it makes sense to highlight and discuss it. And if the criticism comes up when a Democrat criticizes Republicans for the very same behavior they themselves have been engaging in, then yes, it makes sense to bring up Democrat dishonor on the point.
But if it comes up mainly when specific Republican dishonor is being proven, trying to shine the light back on Democrats as being dishonorable in general looks very much like a both-siding strategy intended specifically to neutralize whatever the current specific criticism of the Republicans happens to be at the moment.
Personally, when I see this happen, I see it as an admission by the conservative that the point being made about the Republican has been successfully proven—in this case, that Madison Cawthorn is a dishonorable asshole who's been apparently lying about his own innocence regarding orgy behavior by projecting it onto others.