Managing two different breeds !

How did you go about the initial introductions? From the way your post reads it seems that there was no quarantine done and that the birds were pretty much just put together from the time of arrival of the new birds in the same area.
Adding another bird (the other rooster) to this situation is not going to help. In fact, especially as the bird is a rooster, you will only be increasing the issues you are having now.
I'm not sure why you don't understand that the birds are running away from a bird who has demonstrated a desire to chase and attack them?
It sounds like the best approach for harmony in your flock is going to be to house and maintain them separately - with each rooster having his own hens and the two groups being kept separate from each other - even then, though, you may need to increase your birds as two hens per rooster is a recipe for overbreeding issues.

 

If you want to breed pure breeds, you're going to need separate coops/runs anyway.

Read up on integration.


Here's some notes I've taken on integration that I found to be very helpful.
See if any of them, or the links provided, might offer some tips that will assist you in your situation:


Integration of new chickens to flock.

Consider medical quarantine:
BYC Medical Quarantine Article
Poultry Biosecurity
BYC 'medical quarantine' search

Confine new birds within sight but physically segregated from older/existing birds for several weeks, so they can see and get used to each other but not physically interact. Integrating new birds of equal size works best.

For smaller chicks I used a large wire dog crate right in the coop for the smallers. I removed the crate door and put up a piece of wire fencing over the opening and bent up one corner just enough for the smallers to fit thru but the biggers could not. Feed and water inside the crate for the smallers. Make sure the smallers know how to get in and out of the crate opening before exposing them to the olders. this worked out great for me, by the time the crate was too small for the them to roost in there(about 3 weeks), they had pretty much integrated themselves to the olders.

If you have too many smallers to fit in a crate you can partition off part of the coop with a wire wall and make the same openings for smallers escape.


The more space, the better. Birds will peck to establish dominance, the pecked bird needs space to get away. As long as there's no blood drawn and/or new bird is not trapped/pinned down, let them work it out. Every time you interfere or remove new birds, they'll have to start the pecking order thing all over again.

Multiple feed/water stations. Dominance issues are most often carried out over sustenance, more stations lessens the frequency of that issue.

Places for the new birds to hide out of line of sight and/or up and away from any bully birds.

Read up on integration..... BYC advanced search>titles only>integration
This is good place to start reading:
https://www.backyardchickens.com/a/adding-to-your-flock

 

My first thought is...were the new hens with a male before? Is he trying to assert his dominance and mate with them and they're having none of it?

My understanding is Polish often do not do well in a mixed flock. They look very different, and if their headdress impairs their vision, they can't see behavioral cues from the other birds. You might just need to house your Polish separate.