H1B Stamping in Toronto (Indian passport with Canada Tourist visa)

[dipjyoti]

I am planning to go to Toronto for H1B Visa stamping from US. I am an Indian citizen and I don’t have Canadian PR. My previous H1B stamp expired in May 2020. I am applying for Canada Tourist Visa. I prefer to travel to Canada due to work reasons and I can stay and work at someone’s place. I have a few questions to clarify:

1. For applying Canada Tourist visa online, do I need to upload DS160 confirmation appointment with US Embassy? Canadian immigration officer may want to know how am I going back to my country of Residence – USA since my H1B stamp is expired ?
2. Am I eligible for Dropbox appointment in Toronto without Canadian PR or I have to do in person interview in Toronto ?
3. If due to some reason, US Embassy returns me the passport without H1B Stamp, then I won’t be able to enter US. In that scenario I have to book another dropbox appointment in my home country – India? Or can I enter US from Canada in 30 days even without a US Visa stamp with automatic revalidation. I do have a valid I94.

If there is anyone who has experienced this similar scenario, please advise and I would really appreciate your help. Thanks