Well Luke did say
“Threepio, tell them if they don’t do as you wish, you’ll become angry and use your magic.”
Followed by a demonstration meant to convince the Ewoks that they had an angry god on their hands. Five minutes later C3PO said that the Ewoks had agreed to fight on his side in a war. I don’t see those two things as being separate in any meaningful way.
Also, it wasn’t necessarily in the Ewoks’ best interest to blow up a huge space station while it was still in orbit above Endor…
