So if one of the cylinders is hydraulic locked with oil or fuel how would you fix that issue?
Hydrolock can occur in several different ways so you first need to discover how the hydro-locking is occuring. That means slowly disassembling the engine. The attached photo shows one result of hydro-locking described in the thread at
this link. The piston rod was deformed; the solution was replacing the affected part. The engine still ran despite this damage! Hydro-lock is not the only reason an engine can seem seized. Transmission or engine shaft gears can jam rotation, valves or rings can break then jam piston action; that's why you will need to disassemble and analyze parts if you intend to pursue this line of reasoning.

The rings could be oil-starved so before you start to disassemble, position the moto upright, remove each spark plug, saturate each cylinder with engine oil or fogging oil, do not replace the spark plugs then leave and do something else for a few days. When you come back to the moto, find out if the starter will rotate the engine
with the spark plugs removed, or if turning the rear wheel with the transmission in fifth gear and
the spark plugs removed will rotate the engine. If not, it is likely an orderly disassembly and inspection of the engine could be necessary.