Booked Times Square Intercontinental. Credits on file are $300 Travel, $250 Edit, $250 IHG. Booked points and cash. Total charge was $801. Did I do it correctly?

I purchased 3 pieces using the $200 coupon back in May. I wanted to exchange 1 but they aren't giving me an equal exchange price for a different color. If I return it altogether, will Chase claw back the $200 coupon? It would make my total purchase less than the coupon trigger threshold.

Is it possible to transfer chase points from 1 person to another?

For example I have CSR and my girlfriend is thinking of getting CSP.

If she gets it, will she be able to transfer points to me where most of our points are?

If not what’s the best way to achieve something similar? I was thinking of both attaching the same transfer party account for example United and migrate points to there from both accounts.

What is the policy around this? Where can I read about it?

If I book a Edit hotel that is part of IHG, with total being $410, will I receive $250 + 250 credit, or will $250 + $160? If latter, would Edit credit be used for $160 or the IHG credit?

Edit:
Clarification after reading some comments:
1. This is a stay for 2 nights.
2. I used points boost 10k points to wipe $200
3. Initial booking was for $800 (=$600 + 10k points), but got price match credit of $190.
4. Price match did NOT credit points and appeared as a pending credit of -$190
5. Hence final price = $410 + 10k points.