Parity between Exchange-iCal-Google Calendar

OK - this is hopefully not too convoluted and my posting is prompted by what I understand to be the looming demise of Google supporting their Calendar Sync app (which actually is running on my work sanctioned PC laptop) I presently effortlessly sync my work-based Outlook (Exchange) calendar with all of my OSX and iOs devices. I prefer this set-up as my office based Outlook calendar is gospel I can add something to my iCal and it shows up on my Exchange Calendar and vice versa. I had been using the Google sync app as just another redundant failsafe and run it on my work PC to sync with Google. If I add my Gmail calendar to my OSX iCal accounts it then shows me duplicate entries which I don’t want. Is there a way for me to still have my Exchange sync with iCal and then sync with Google calendar? I just want to I suppose “ricochet” my Exchange data onto Google via its initial landing on iCal and not have the redundancy of entries appear on my calendars. Is a one way of data submission possible? Or is this all for naught and will in fact the Google app still sync but it is just that Google will no longer support or develop the program moving forward? Any and all suggestions welcomed Thanks