I think it’s simple enough using the :advanced filter. You need to change the year for each user to the year where the event is happening and check whether the birthday falls within that range. Otherwise the date comparison would be off.
I assume “Lauren’s” birthday is 05/06 if it should show though, not 05/05.
If you have an event with a start date and an end date, data source for RG should be:
users:filtered:advanced: this user’s birthday:change year to:[event-start-date-extract-year]>=event start date.
users: filtered:advanced: this user’s birthday:change year to:[event-end-date-extract-year]<=event end date.