u/Putrid-Boss5828

I bought a new Bosch rs325 reciprocating saw today to remove an old hot tub. After installing the blade (also new) however, the collar doesn't come all the way back to its original position. The blade seems fairly well held in place, I can't wriggle it free. Should I return it all the same?

Found these while dismantling an old rotten hot tub in my back yard. I pulled out a few wood planks and noticed the wood (and oddly enough the hot tub foam) was full of tunnels with these things crawling through them. Should I call up the exterminators asap? I'm located near Vancouver, Canada.