Not sure this is exactly what you're asking but only today I had reason to copy animation keyframes from one length of spiral party ribbon to another and which was not identical mesh to the first.
This copy/paste method should also work in you case so I'll outline what was done firstly, then come back to your situation.
Both ribbons were required to be bouncing up and down, expanding and contracting etc. as party ribbons do.
The new ribbon was not animated so it was given a dummy 'location' keyframe at frame 1 in order to have it appear in the Dopesheet.
The original ribbon's keyframes were then copy/pasted into the new ribbon's strip. (CTL-C/CTL-V)
That involved the timeline cursor being set to a frame a little past it's location keyframe at frame 1. I chose frame 11.
The 2nd model's title in the Dopesheet needed highliting for the paste operation's destination.
The 2nd model's strip(s) accepted the animations and whatsmore they worked. The original model however also got a copy of the same keyframes and that's when it's 'wheels fell off'!
The work around was to deselect every new keyframe in the 2nd streamer's strips and what was left highlited were then deleted.
That cleared out the trouble makers affecting the first streamer and it reverted to it's old self and worked fine.
Now back to your question -
If you append not just your model but the entire scene into the 2nd Blend file as I do, that might help, but it's only a guess. What have you got to lose?
When you copy/paste the first model into the 2nd file's FIRST scene, and into a spare layer, it's animations keyframes should appear in the Dopesheet.
These should then be copiable into the second model's strips as I've outlined above.
Recall that I inserted a dummy "Location" keyframe for the 2nd model just so it would appear in the Dope sheet. What surprised me was that when the 2nd model (ribbon) accepted the copied keyframes, it didn't take up the identical location of the first!
It remained where it was and started animating from it's own location. Was that because of the "location" keyframe at frame 1 ?
If your 2nd model has no animation it would also require at least one keyframe to get it appearing in the dopesheet.
Given that you're having trouble with the rotation and location, try inserting keyframes at frame 1 for all three, rotation, location and scaling.
Move the timeline to say - frame 11 and copy paste all the original model's keyframes into the 2nd model's strip. Left click on the 2nd model's overall 'action' strip to highlite it and do the paste. (CTL-V)
The keyframes will copy over, and in your case the troublesome extra copy in the original model's strips wouldn't matter because you'd be deleting that model anyway. If not do as I did to eliminate the problem.
At present I don't have time to test this with bone animation but I would imagine the mechanics would be the same.
If you try this, let us know how you get on...