Distance marker stake | Golf Monthly

Unless the distance marker is deemed an immovable obstruction in the local rules, you can lift it out.

The hole in which the stake is set is a hole made by a greenkeeper and thus by definition an abnormal ground condition from which you can take free relief if there is interference to your stance or area of intended swing.

There is no penalty for moving your ball when removing an obstruction.

Despite your 99% certainty, you could have been clear of all difficulties at no cost.