Firstly I'd try moving the first nap later and then knock on the second would be later.
Also given in a few months the move will be to 1 nap... As long as the morning is in the Cot, of the afternoon nap in the pushchair works, then why not do that, why make life harder...or why make a problem where there doesn't really need to be one.
As I got told when mine were babies, we need to look at our real goal, which in this case is a good afternoon sleep so as not to need a catnap, it's not to make sure it's always in the cot... So I think in many ways an unimportant belief may just be part of causing your problem. So tbh I'd go back to trying the nap in the pushchair if that was working.