Reviving Old Subreddit

A couple of weeks ago, I was accepted as the new Mod for an unmoderated Subreddit.

It has about 3,000 members. The previous mods used super strict settings so there was no activity when they stopped moderating it.

The community is great for an offer I have and I want to use it for parasite SEO and long-term affiliate sales.

How do I get engagement to pick back up? Should I post from alt accounts until others start posting? Do you think once per day from alts enough? Is there a way to message all the subreddit members or send some sort of notification?

I was thinking I can find an old top-rated post, paraphrase it, and then send a few upvotes and comments to it as a start.

Does anyone have experience taking over a subreddit and getting it active again?

Post there and crosspost to related subreddits.

Yeah you can post with alts some content to make it seem more alive. Also with those alts crosspost to other subreddits.
Post a few posts a day with different accounts and crosspost one or two to other subreddits.

When you post something users that are subscribed to your sub will automatically get alert for new post in your sub.

Find similar subs, figure out your demography, start posting what you think that demography wants to read, then start crossposting. There's really not that much science behind it.

Can u share the rest? Im interested. thx mate or send links to new reddit posts.