I assume after the freeride? It’s okay to run it for the week then flush at the lake. Correct? Thinking of fogging it after each day. Then flushing it at the lake before the trip home.
Yes, ski will be fine for the free ride without flushing each day. Blow water out the exhaust after each ride. When you're done for the day, spray it down with SC1(or something similar) and leave the hood off / vented to breathe. Flush on last day at a boat ramp/harbor / lake.
I ride surf / salt 99.9% of the time. Riding one weekend in salt will not ruin your ski. When we go to Pismo Freeride or Mexico, we do not flush for 3-5 days. The comment on tearing your motor down after salt use is hilarious.
If you're worried about electronics in salt, the big thing is making sure your Ebox is properly sealed. Put dielectric grease in the connections for start stop. Make sure your battery cables aren't $hitty. Those are the big three for me. Based off your first post, looks like you've done more than enough to make sure your ski is salt worthy.
A lot of people overthink prepping a ski for salt. As long as you're stuff isn't ghetto rigged or junk, I guarantee you will be fine. Salt is just less forgiving for existing issues that freshwater can't find (slits/tears in wires, battery cables, etc.)