Have you tried copying the files directly from your SD to computer and thereafter to an app such Dropbox and there after transferring files to your IPad. I have no problems running 4 K video ex Mavic on my iPhone 11 or IPad Pro. Hope this helps.
Hi glad at last to have time to participate in the forum. Have been occasionally loitering from 3 years . Have flown P3 P4 and currently flying a Mavic Pro. Hope to make a contribution.
Best Des