From what I’ve read Poland rebuffed any suggestion of a joint defensive treaty with the Soviets. No one had seen the Nazi war machine in action yet and the Poles thought they’d rather go it alone with only British and French promises.
Why would they? The Soviets invaded them in 1920 and were rightfully just as worried about them as Germany.
Stalin was demanding that about 2,000,000 Soviet troops were to be placed in Poland. Poland thought that if they’d allow it then the Soviets would never leave.
Quite justified fear as after Estonia, Latvia and Lithuania allowed Soviet forces on their territory as part of a similar treaties the Soviets used these forces to invade and install puppet governments.
They correctly considered the Soviets to be worse than the Nazis.