..try playing just the top three notes of the LH chord (A#, E, F#). This is easy, no? Then, while holding these notes (using them as a pivot point) try to pivot your hand to the left while extending your pinkie (so that the bones of the finger are parallel to their corresponding bones in the hand), to reach the low 'F#'. Reaching the low F# while holding the little note-cluster at the top, is the technical problem to solve, not trying to reach that 'E'. .
At the risk of boring the rest of the forum to death I'll persist with this...
I tried what you say above but with the help of a tape measure I find that the simple truth is that the distance between keys F# and E is 14cm. The distance between fully extended pinkies no.2 & 5 is 13cm. There is NO WAY I can achieve that stretch without E flat playing along as well! As you say, the technical problem is the lower F#. No problem with the A#.
Not to worry, I'll just play my version as before.
I don't get bored with this line of conversation! (I'm a teacher rehabilitating an injury that occurred months ago, so my patience is unnatural.)
Have you tried rotating your left forearm counterclockwise to about 45 degrees and playing the low F# on the pinkie's left edge? There's a bit of gymnastics involved but if one can orient the hand and arm and fingers in such a way...so that you play on the left edge of 2 and 5...the chord is likely reachable. Try experimenting with some unorthodox ways of extending your pinkie and index finger (namely, with a greatly supinated hand.)
Luckily, the reach between 2 and 5 can be increased due to the fact that the hand is stretchable (even if you're old!) but don't go injuring yourself like me.