If LAC is in fact "interested" in Simons and willing to make a deal that includes Zubac, I say go for it. Sure, you are trading some back court depth for front court depth, but Zubac is likely a starter for BOS. I would rather have a starting Big over a back up guard.
There would be many options as a follow up move to bolster the back court depth. Dosunmu would be one avenue but not nearly the only avenue. Absolutely, if you can finagle Zubac for Simons, do it, and then sort out the rest.