Boomerang to Old Company in 2 months?

This is kinda weird and unexpected - It has just been a couple of months since I left my previous company (a Unicorn) from a senior role in business. I left on good terms due to reasons like : Lack of personal growth in sales-led roles and being in the same industry for long.

I had just moved from BLR to Gurgaon to a new startup (run by a conglomerate) and it has not exactly gone as per my expectations - no Hybrid WFH option (WFH is not very common in non-tech domains too); extreme micromanagement and the weather+vibes in Gurgaon (no offence please).

Now, my previous company has called me back for a strategy role. I'm super confused:

1. I prefer BLR any day
2. I prefer working in Hybrid mode any day
3. But I left my previous company due to stagnation in sales roles. The role offered to me now is a Strategy+ Partnership one.
4. I am not exactly sure how I will tell my current employer about this. It will be a dark mark?