By raiding Mar-A-Lago, they just showed their hand...and revealed that they are weaker than we thought they were.
Fear and panic can cause a person to not think straight.
And act irrationally.
I think the OP may be on to something—and probably the exact opposite of WH claims is what happened (the rule of opposites).
That would mean the planted “evidence” was debated around the Just Us Department and the White House by staff—probably a big email trail and a bunch of meetings discussing whether it was real or not.
My guess is that the decision was not unanimous or even close to unanimous, but the majority of the Ruling Central Committee decided to “take a chance” knowing the mass media would have their back in the worst case.