Yes.
Surprisingly, it (the older 5344 and newer PT tender) works just fine.
I have that very combination sitting on my layout at this moment. It sounds just
great - except that it still only has one chuff per revolution, as that is triggered
by the loco; on my List of Things to Attack.
Here's the trick (it was just logical): you must do a simple factory reset on
the loco, but when you put in the number "code", use the number from a "modern"
loco, and I believe that it's 74 (look in a recent loco manual or the Lionel webste, I guess). This resets the loco sound protocols to talk to the new tender. It works just fine, coupler and all. If you don't do the protocol change, the tender will just "idle".
Also:
Second good thing: you now have this beautiful Vanderbilt tender (that needs re-
lettering, of course) that will work behind a "new" loco:
I took my freelance Hudson (used to be a too-long Lionel Erie Pacific) and did a factory
reset to an "old" number (18, I think...) and the newer loco now talks to the older
Vanderbilt just fine. Looks good, too.
Haven't re-lettered that pair, yet. (Don't forget to change the number on the back
of the PT tender; cab chatter will be wrong, but I never use that stuff anyway.)
BTW, my Pullmor-equipped 5344 actually is a very sweet runner, and I'm not a fan of
the old motors, so much. It must have decent gearing - but it does take 2 or 3 trips
around the layout to "warm up". The PT tender is correct and looks great. And I love those Scullin drivers on the loco.