I went down this path, but for invasive red mushrooms. ive arrived at this:
there are two possible outcomes in your situation, and one of them works every time to rid your system of the invasions. the other varies
after majano wanding myself sick and buying two diff units off
amazon, only to have the partial pedal tissue leftover just regrow, I finally opted in to the guaranteed fix method of removing the rocks from the tank and using a screwdriver to chip off each anemone, anchor point included
in the end my rock looked scarred but it was free of anems
two weeks later I noted some missed stragglers, arising from the leftovers Id missed. removed rock, took just a fraction of the time to locate them and scrape. within two attempts a 3 yr scourge was removed from my tank.
the variable method is anything other than that, this includes all anemone invasions not just red evil mushrooms.