Only JH can explain exactly what he means, but I would take it to mean that he's scared that the extreme focus in the early days has died down. LE searched for about a week, Texas Equusearch came and went. The investigation has probably gone more behind closed doors, so JH can't 'see' what's happening and that sometimes makes people feel that everything must have stopped, or almost stopped, because it's not what they saw in the first few days, the first week. People are likely to feel worried that 'their' case is being pushed down the priority list as information slows to a trickle and other big cases come into the police department and take up detective-hours. I think a lot of people get that feeling and end up saying similar things to what JH said there. The public often make similar comments and can be extremely judgmental against LE, people become backseat drivers, they compare one case with another (imho they often compare apples with oranges).
I don't think he's intending to be offensive with his comments.
My concern is how good are most private detectives? It seems rather hit-and-miss for a lot of money, some seem very shonky, some I'd expect to be better as they can be made up of retired detectives who have a very good history in LE.
But I can understand people in this situation wanting to feel like everything is busy and active in the investigation, and getting concerned when that activity stops being as ''in your face'. I think we need to remember to have empathy for relatives in situations like these.