I'd say odds of SAM unit being at least listening to airport radio traffic at 1/2 best. Actually being in direct two-way contact (without relays in command structure) less likely than that
That's not surprising.......back in the days when GF operated a BAC111/B737 service to Shiraz (1970's) a civil aircraft on final approach might see a couple of fighters climbing out towards it just after taking off. There were 2 ATC units, one civil (broken English) and one military (Farsi), and it seemed that they didn't talk to each other while controlling their traffic on the single runway. Winds were usually quite light, so the runway in use by each ATC unit was not necessarily the same.