@Linda3182. Hi Linda, I'm so sorry to hear this. We keep our wifi, alarm and external wired cameras set up behind a locked cupboard bolted to a wall so they would need to do a massive de construction to get at it. All three are connected to apps only we can access, plus the smart door. We get instant warnings when anything goes off, including power.
I assume you have it in your House Rules that the wifi is not to be touched or switched off as its essential for running utilities?Talk to a security guy about an upgrade. I know its not cheap but you are permitting strangers onto your valuable property.
And give a very factual and detailed review of the guests as well as flagging the host on Airbnb system on their own listing, based on their rudeness to you.
Hope for the best but always plan for the worst. Good luck.