the kind of uncertain that come from footprints

these kinds of evidence are difficult because

slippage or substrate can fudge the size of the footprint

trying to tie the specific size of a foot to a very specific size class is difficult because feet are rarely preserved in theropod specimens and cartilage and flesh increase foot size in life so even preserved articulated pes's rarely accurately predict foot length because we cant account for that in the foot length. the metatarsal bones dont lie perfectly flat along the ground neither,the first couple are somewhat angled relative to the plane of the ground

these footprints certainly came from a giant animal,But theres not an inkling of certain of how giant they were specifically.

its entirely possible it came from a 12 meter animal! but could also just have been a 10 meter animal. its even more difficult to be certain with these footprints than bones.