Jesus left Tyre and went around to the borders of Decapolis (which included Hippus on your little map) then approached the sea of Galilee from the back side. Is there some kind of law against that?
Is there a law that Jesus had to follow some straight line route to get where he was going? And if he was going to the back side of the Sea of Galilee, wouldn't he have naturally taken this route?
Frankly the fact that this detour is mentioned is evidence of its truth. There was a reason why this was mentioned. The detour was important. Everything in the Bible is important.
Why was it important? Roberston's Word Studies gives us some insight:
Through the midst of the borders of Decapolis (ana meson twn oriwn Dekapolewv). Jesus left Phoenicia, but did not go back into Galilee. He rather went east and came down east of the Sea of Galilee into the region of the Greek cities of Decapolis. He thus kept out of the territory of Herod Antipas. He had been in this region when he healed the Gadarene demoniac and was asked to leave.
This matches the TR text. Apparently, there is a textual variant between the WH and others. The Byz agrees with the TR. I looked for my UBS, but I must have it at the office.
The "dia" associated with Sidon doesn't necessarily make anything wrong, because that might well have been the direction Jesus chose to go.
There is nothing that requires Him to go on a straight line from Tyre. Nor is it said that He does. In any case, it appears to be a continuation of a journey into predominantly Gentile country.
CDL teaches Greek, so if he comes online maybe he can clear it up.
So far as "bible scholars" is concerned....presuppositions makes all the difference in the world.