Icejade Interactions (Aegirocassis)

I am rather new to yu gi oh still and i have been having issues with certain card texts not being clear (EX. some pot of cards must be the first spell used but it doesn't say this on card text.)

I am trying to make an ice jade deck as the artwork is nice but i am having an issue in masterduel where Creation Aegirocassis is not working as the text says.

send Aegirocassis to GY

summon Ran Aegirine and create token

synchro gymir aegirine

cast pot of desires and banish 10

attach Aegirocassis to gymir

gymirs stats do not change despite now having 4 monsters in the banish zone

Aegirocassis only states "for each banished monster" is this supposed to include only my opponents banished?