Quick Question for some Lambda Chis

[DeeZeeOE07]

On my campus we still sort of do big bros/little sisters and my boyfriend wants to be my new little sister's big bro. All this really means is they get shirts made but he's kind of excited. I wanted to do the shirts like this:
Her shirt with Delta Zeta greek block letters with Lambda Chi Alpha in english going across it. A Chop here that I'm friends with said it was against their rules to do that but a lot of girls have shirts made like that who aren't dropped or sweethearts. So I'm wondering if that's a national rule or just their chapter? Also, for his shirt I'm doing the same thing but the opposite, (Lambda Chi Alpha greek letters with Delta Zeta in english) My president said it was allowed from our side but is that ok for him to wear that? I wanted to know before I got them made. Thanks!