When someone cuts a friendship off, advice?

The 1st cut off was because of the rumor and he liked you.

The 2nd cut off was because you friend-zoned him.

Either way, let them both go. Don't let it bother you. The last thing you want is to become obsessed and vengeful.

Observe the girl's bathroom rituals. Get to know when she usually takes that break. Once you can reliably predict when she will go to the hoops, hatch this evil plan: Bring print outs of "out of order" for your bathroom stalls. Enter the restroom she uses minutes before her. Tape the signs on all stall doors except one. Bring 2 ketchup packets and fold them in half, placing them under the small dome pressure points of the seat. Linger around bathroom door listening for shrieks. Once you hear her shouts of joy, pull the fire alarm. In the throng of exiting co-workers, slip some of the "out of order" printouts into the guy's cubicle, then mention to the boss that you saw that one guy pull the alarm.

Burn your workplace to the ground with him inside, then get 'rumour girl' framed for arson and manslaughter.

Not worth your time. Be with people who are worth your time.

It's ESSENTIAL to avoid drama at work. If an employee keeps getting caught up in drama, some bosses will decide that the employee is the problem even if they are not at fault. It's nice to have friends at work but a lot of the people at work like to keep their enemies close so they may not really be friends. It's smart to have professional contacts at work but many friends from work will disappear as you move to new jobs.

Spread the rumour that your jealous work colleague was caught giving your supposed friend a blumpkin in the bathroom.

Fuck the both of them and then ghost them

Just kidnap him, that's the best way to fix a relationship.