It might work if you use policy-based routing for the 192.168.1.0/24 destination on the LAN interface, bypassing IPsec.
It's a big might.
It sounds like you tried that though. You might want to post what you've tried because, at a minimum, that should at least send the traffic out the correct gateway instead of IPsec.
That's why it is not recommended you configure large swaths of space like 192.168.0.0/16 anywhere. Running into conflicts with other sites is pretty much inevitable when you do that.