2000 Honda Accord head gasket replacement

A 2.3L accord came into shop; heater hose from engine to heater core split and leaks under pressure from gauge.
customer drove vehicle not paying attention to gauges for some time and noticed overheating condition. Vehicle cooled and started engine to add water. Placed radiator cap on and squeezed rad. Hoses, noticing lower hose under pressure and upper hose had collapsed as if under vacuum. Tested coolant with BLUE combustion leak detector fluid and fluid DID turn YELLOW. After wards, the fluid returned to its blue color. Is this normal for fluid to return to blue color? Oil is not a "milky" liquid. My concern is a small crack in cylinder wall of block and do not want to recommend head gasket (and new head probably due to it being aluminum and overheated) and I am asking what the proper procedure would be.

Customer requests new hose and authorizes diagnostic, however I'd like a professional to guide me in this situation please. What to look for first, and last. Customer vehicle is her mothers and will probably not be repaired at our facility, yet i'd like to be able to guide them in the right direction and not replace motor if not necessary.