Well, I think we have a root-cause. You don't necessarily need to install OpenWrt in order to fix this... you just need to make sure that the DHCP server is disabled on your AP (or if you cannot disable it, at least make sure it advertises the correct gateway and DNS addresses, and then disable the DHCP server on your router (there should only be one DHCP server enabled on the network).
Given this, I suspect that your problem is solved (at least from the perspective of this thread)... is that correct? If not, please explain what other issues you have. But if it is resolved...
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