Landlord Warning About Police Entry During Drug Dog Training

Hi all, this is my first time posting to this subreddit. But I desperately need advice.

Location: Montana

I signed a year long lease about 6mo ago with two other roommates. In the original lease it states that smoking on balconies is prohibited and that we must be 20 feet from a building for it.

Today, our landlord sent out this text (copy and paste)

Hello (complex) Residents, in the coming weeks you may see K9 police officers with their dogs in the buildings and hallways. If you see them, pls don't be alarmed, they are training drug dogs for searches. They will not go inside any apartments - unless of course they found something. Pls remember even though pot is legal in Montana, it is not allowed inside or near our buildings, and we have asked them to notify us if they find pot being smoked as well.

And in our lease it reads this on the topic of drug use:

Pur uant to Section 70-24-321 of the Montana Code, you, your occupants or guests, or the guests of any occupants, may not engage in the following activities: criminal activity, behaving in a loud or obnoxious manner; disturbing or threatening the rights, comfort, health, safety, or convenience of others (including our agents and employees) in or near the community; disrupting our business operations; manufacturing, delivering, possessing with intent to deliver, or otherwise possessing a controlled substance or drug paraphernalia; engaging in or threatening violence; possessing a weapon prohibited by state law; discharging a firearm in the community; displaying or possessing a gun, knife, or other weapon in the common area in a way that may alarm others; storing anything in closets having gas appliances; tampering with utilities or telecommunications; bringing hazardous materials into the community; or injuring our reputation by making bad faith allegations against us to others.

And for more context other than this, we are 21, 20, and 20. There is indeed weed in our household and we are relocating all the bud and any other paraphernalia. The only thing that is remaining in our apartment is a mostly empty cart (from a dispensary) and a battery.

With all this information, what legal rights do we have in the case of 1. The dog alerts and (can) the police legally search our home due to a TRAINING drug dog? 2. They do search and find a singular dab pen in a household with two people who are technically underage, as the legal weed usage age in Montana is 21. Can the person who is 21 be held liable under the minor exposure laws? And 3. What rights DO we have as tenants in this situation??

Any advice is welcomed, we are very worried as a household.