Wow, can't really put him on a hand... nothing makes sense
Best I can do:
- 64/54s [4 combos] who got stubborn on the flop and very stubbon on the turn
- AA/KK [18 combos] who was calling down and then got carried away with beating 97 after the board paired
- QQ [6 combos] went for a risky check/call turn, check/raise river
- 97s [6 combos] , 99, 77 [12 combos] who decided to slow play all the way (and in the case of 97 then went for a bluff against your supposed overpair after it got counterfeited).
But all the 28 ahead cases seem unlikely (97 too aggro, 54/64 too passive, AA/KK to passive till river then too aggressive) vs 18 vaguely plausible behind cases.