It may not be clear, but what they're saying is that the problem your encountering is more to do with the HTTP response from the server, not the client (Arduino device). You need to wrap the response in something. In web programming the server would spit out a rest JSON formatted response like:
{ "Time": 1001010}
Not ideal to deserialize JSON, but if you just spit it out by itself, then you could say the entire reponse body is the time. Or a comma or pipe delimited string that Arduino could turn into an object and it's properties. I do REST API's for a living basically. Usually serving data to Angular, Vue or whatever framework. They all handle JSON docs, I've played with the JSON library for Arduino, but it seems like it's CPU heavy where it's most useful or overkill in a scenario like yours.