Will ppl know? honest only

I honestly wouldn’t worry about this, most people who aren’t in Greek life don’t know/care about rankings, and even if someone does care, if they judge you for being a part of a house that you love then that’s their own problem

both the houses you mentioned are known for racially biased recruiting and dirty rushing. and many pi phi’s drop within the first year cause of poor sisterhood/cliques within the house.
don’t stress about alleged “tiers” cause
greek life is chill here.

lots of people know the general rankings but VERY few people care. and the ones that care usually don't understand how over-dramatized the differences between houses are and they are trying to gauge your social status on something that's not even a very good predictor of how cool you are, whether that be looks or personality. there are 10's in bottom houses and 2's in top houses (on both looks and personality scales) and if someone is looking to your house label as a way to judge whether you're interesting enough to engage with, they clearly don't know how to look for good people in their life and they're just gonna be confused.

If this is something you actually care about then drop Greek life