Why would a lawyer knowing lie in a verified Complaint

Location: Arizona

I am currently in active litigation with a co-owner. Opposing council filed an ouster claim against us, which is untrue; there is no evidence supporting it and the his client has freely accessed the property. We have previously sent him photos and videos of his client freely using the property, so it isn’t like his client lied to him and he is oblivious. When we get to discovery, he will not be able to provide dates or times of exclusions, because they don’t exist. I am at a loss for why a lawyer would risk filing a verified complaint when they already have evidence that defeats it.