This is just to update in case this might be helpful to anyone else having the same issue.
I contacted other techs of my website host and they had me delete and restore my website.
This resulted in my not being able to access my WordPress dashboard at all (any of the admin dashboards of all the sites in the multisite network).
I was then told by a senior tech that the issue was an incompatibility with a WordPress security plugin (https://ww.wp.xz.cn/plugins/all-in-one-wp-security-and-firewall/) another outside developer had installed to help my website.
The plugin has the “Ability to hide admin login page. Rename your WordPress login page URL so that bots and hackers cannot access your real WordPress login URL. This feature allows you to change the default login page (wp-login.php) to something you configure.”
This is what caused confusion and prevented me from accessing the network admin dashboard as it is installed on there.
I used deleted the plugin database folder via FTP (FileZilla).
Attempted to access my WordPress site dashboard via my website host dashboard.
Upon being directed to the WordPress admin dashboard login, I reset my password.
I was then able to log in (and taken to my primary website dashboard)
But it appears that in order to access all admin dashboards of each site on the multisite network — including the network admin dashboard, I needed to click on each site’s dashboard.
I clicked on the second website’s dashboard, was redirected to sign in, signed in with the new password and was redirected back to that site’s dashboard.
I was then able to click and access the admin dashboards of each of the other 3 dashboards.
And then — the best for last, I clicked on the Network Admin dashboard, was redirected to sign in, signed in with the new password and was finally redirected back to the Network Admin dashboard with full access and no issues.
I think signing into one of the sites that is not the primary site is a key element in the steps. It might somehow “activate” WordPress to recognize or re-establish the site network so that you can then sign into and access the network admin dashboard.
I know this is a lot but I hope this helps someone as I know how it can be stressful for those of us with websites who are not very tech-savvy.
Thank you for all the responses 🙂
PS I also found that some WP security plugins can be troublesome with multisites in this way. A helpful read for how to navigate this:
https://ww.wp.xz.cn/support/topic/not-working-on-multisite-32/