Use the attached id_match predicate and try the following (with a scoreboard called ids):

1. Set $tempID ids score to something inside of the range [-43,160,000, 43,160,000].
2. Set the player's score (or the score of any entity) to the same number.
3. Using something like /say @e[predicate=something:id_match] will allow the predicate to find the entity,
4. Set the scores to something outside the range above will not work.

The scores of $tempID and any other entities should match, of course, for this to work at all.

This is probably also broken in every version since this predicate type was introduced but I don't have time to test them all. ^^'