Ask UEFL - Who Gets a Strikeout in a Suspended AB?

This edition of Ask the UEFL concerns a suspended game between Oakland and Detroit: which batter gets the strikeout if an at-bat is interrupted by a span of days, weeks, or months?

A's pitcher Liam Hendriks faced Detroit's Josh Harrison at Comerica Park, Michigan on May 19, 2019, as rain began to fall in the bottom of the 7th inning, just as Harrison ran the count to 2-2. Crew Chief Mike Winters and HP Umpire Tim Timmons pulled the teams off the field for a weather delay that turned into a suspended game when play could not be resumed.

The game finally resumed on September 6, 2019—nearly four months later—during the two teams' final meeting of the year...in Oakland. Detroit remained the home team (albeit wearing visiting uniforms for logistics reasons) and Jordy Mercer assumed the remainder of Harrison's at-bat with Hendriks remaining on the mound for Oakland.

Mercer swung and missed at the first pitch he saw from Mercer, thus completing the four-month-long AB, but who gets the strikeout? Mercer or Harrison?

The answer, pursuant to Rule 9.15(b), is Harrison: "When a batter leaves the game with two strikes against him, and the substitute batter completes a strikeout, the Official Scorer shall charge the strikeout and the time at bat to the first batter. If the substitute batter completes the turn at bat in any other manner, including a base on balls, the Official Scorer shall score the action as having been that of the substitute batter."

And although Hendriks played both halves of the suspended game, had he been substituted for, Rule 9.16(h) is quite elaborate as to which pitcher (original or reliever) would be credited with a base-on-balls had a walk occurred: For any 0- or 1-ball count, the reliever is responsible for anything that happens, while the preceding pitcher is responsible only for a base-on-balls when he leaves the game with a count of 2-0, 2-1, 3-0, 3-1, or 3-2. Anything other than a walk—a hit, error, HBP, etc.—is charged to the relief pitcher.

Instructional video as follows:

Alternate Link: OAK-DET game falls under suspension due to rain (CCS)