There is no reason to wave a Palestinia flag at all. Just use signs Calling for restraint and help for the civilians.
No, the point in waving a Palestinian flag is to support the recognition of an independent Palestinian state. You can support that without supporting the terrorists that appropriated it.
Personally, I’d like to show up with both an Israeli and Palestinian flag, but I’m worried I’d just be jumped by the extremists on either side. I think a two-state solution must be the direction we go, not just “restraint and help for civilians.” Both Israel and Palestine must be independent, but getting there is an incredibly difficult thing that may not be possible without serious concessions from both sides, which isn’t likely to happen with the current leadership on both sides.