Tosefet Bracha Shelach Lecha part 1

"Send for yourself men” (13; 2)
Rashi points out the reason that the story of the spies follows immediately after the story of Miriam (at the end of Beha'alotecha), since they both speak about lashon hara.
It is not clear to me why Rashi has to point this out. There are many sections of the Torah that we never ask about the reason for their juxtaposition, so why does Rashi need to say anything here?
Perhaps we can say that this juxtaposition requires particular explanation, based on the Talmud in Shabbat (116a) that it is not correct to put two bad topics next to each other. Here we have the tragedy of the spies immediately after the tragedy of Miriam, and this requires explanation. Therefore Rashi explains that they both deal with the same topic of lashon hara.

"Moshe called Hoshea bin Nun - Yehoshua” (13; 16)
We must point out that every time in the Torah and Nach that the word 'ben' appears it has three dots (segol) under the 'bet'. However, every time it says Yehoshua's name there is only one dot (chirik) so that it is read as 'bin'. This is strange. There must be some special reason for this unusual vocalisation.
There is only one other time that the word 'bin' is used, and that is in Mishlei (30; 1) “These are the words of Agur, son of (bin) Yakeh...” when the 'bet' also has a chirik. [There is also another time in Parshat Ki Tetzei, Devarim 15; 2, but there it doesn't mean 'son', so perhaps that is why the author doesn't mention it.] The Sages have discussed this in the midrash, and explained it aggadically (metaphorically) in Shemot Rabba Parshat Va'era section 6. However the explanation there has no relevance to the verse here. The Sages appear to say nothing at all about our case. Nor have any of the commentaries discussed it, and this is extremely strange.
Perhaps we can explain based on the Talmud (Sanhedrin 107a) and midrashim that say that the 'yud' that was taken from Sarai (after he name was changed to Sarah) complained about being removed from the Torah. It was only consoled when Moshe took it and added it to Hoshea's name to make Yehoshua (by adding a 'yud'). In this way the 'yud' that was removed from Sarai was replaced into the Torah.
This Talmud still leaves a difficulty, because even though Moshe found the 'yud' to add to Hoshea's name, where did he find the vowel to go under it? The 'yud' from Sarai had no vowel under it, whereas the 'yud' of Yehoshua has a 'sheva', which is two dots. We know that the number of dots in the Torah is precise and exact, so how could Moshe add two dots to the 'yud'? Therefore he had to remove the two dots from the 'bet' of 'ben' and replaced the 'segol' with a 'chirik'. This left two dots extra which were used for the 'yud'.
Even though this explanation is subtle and unusual, nevertheless, because of the uniqueness of the vocalisation of this word you should accept it.
[This doesn't explain why he was called Hoshea 'bin' Nun before Moshe added the 'yud' (verse 8) – perhaps the 'segol' was already removed in advance of the name change?]