Has any institution refused to honor your POA?

Rather than just bringing a bunch of people with you.

I would gather up all documents that you have that states that you are your friends' legal Durable Power of Attorney, and bring to them to the local or county Sherriffs' Department and request that they escort you into the building to see your friend.

If you haven't done this already I would advise the Ombudsman that your visitation has been restricted. A resident has a right to visitors and to refuse visitors. A POA doesn't necessarily guarantee your access to the building. To avoid unintended consequences of disrupting other residents or having the facility file a restraining order, I would see if the Ombudsman can help with an amicable resolution.

Wish I had the answer talk to Pam Stegma she is an ombudsman

Let him call the police! As long as you have a notarized POA you have every right to act in place of the person for whom you hold POA.

Go right back to the same person you made the first complaint to (ombudsman), and let them know whats going on. This is terrible, the place needs to be shut down! Knowing you have a complaint against them, they should not be treating you this way! What was the 1st complaint about? Your friend is depending on you, don't be bullied!

Retaliation while being investigated -- pretty sure that is not allowed under some state law, I would go to the Ombudsman program, the very same person or place where you filed your complaint, and file another complaint. BE SURE you have documentation of how the ALF behaved or exactly what they said, perhaps ask them "I don't understand why you won't let me visit my friend, and I do have their POA, can you please provide me your answer IN WRITING so that there is no misunderstanding? " make sure that person signs their name & position in ALF. then when you get their note that you are not allowed to visit, you have PROOF that can be used against them. Anything else is "he said - she said" territory. Unless you have a bunch of disinterested witnesses (NOT your friends )?

Do you have an iPhone? You can video him harassing you... if you think you need proof!

I have run into this, where a bank would not accept my POA, DURABLE & ever kind I have untill I got a letter from a shrink to state I was MENTALLY OK~I saw to it that the person who subjected me to this was fired.
I received a letter of apology.
Only once that has happened to me. I am 69. The person who attempted to pull off this stuff was 20 years old.

...and not very well trained, informed or educated.

You got the last laugh.