This is such a stupid idea I hope they go forward with it. The DNC now has to PROVE what their allegations. There is no universe where this works out well for them.
No matter what the outcome:
1) Trump will still be POTUS
2) Hillary will NEVER be POTUS
3) If they lose or drop the suit, Trump gets to FLAUNT the fact that they CAN'T PROVE ANYTHING
4) When Julian Assange states in court that his source was the murdered DNC staffer, their case against Russia goes to shit
5) It opens up EVERY LETTER that Dead Ted wrote to the Kremlin about a quid pro quo with primarying Carter and/or defeating Reagan, so their treason charge goes away (They can hold to it still, but they'll have to throw away all the current Kennedy clan who are in office)
6) It still depends on Mueller finding something
Cue what Napoleon said about mistakes...