Masbooq (latecomer) joining the Imaam before Salaam

Q: Whilst performing Salaah with Jamaat behind an Imaam, if a Masbooq (latecomer) joins the Salaah after the Imaam has completed four rakaats and joins just before the Salaam.

1. Is it necessary for him to recite the tashahhud with the Imaam for his Salaah to be valid or is it sufficient for his Salaah to be valid that he joins in the Salaah before the Imaam makes salaam?

2. Should the Masbooq recite only Tashahud in the Qa'dah or also Durood Ibraaheem and Duaa after Durood.

Experiencing a discharge due to sexual thoughts

Q: I was at friends house and some of her guests were saying inappropriate (sexual) things and I was trying not to listen but when I did, I got weird feeling in my private area and like something should be put up in the area (private area) but I didn't. I just sat there till the feeling left and when I came home, I went to the washroom and I had a bit more discharge than usual like it was kind of a lot. Should I do ghusul?

Delaying in performing the Janaazah Salaah and burying the deceased

Q:

1. What is the shar’ee ruling in the situation where a foreigner passes away and his family from his home country makes a request for his body to be sent to them. In this case it is a legal requirement for a chemical to be injected into the veins of the deceased to keep the body from decomposing. Is this allowed in Shariah since it is a legal requirement?

2. If a foreigner passes away and his family from his home country makes a request for his body to be sent to them, then before sending the body overseas, do we have to carry out the ghusal, kaffan and perform the janaazah salaah? Once the family receives the body, will they have to repeat the ghusal and janaazah salaah?