Here on the Atlassian Community, we can help answer questions about Atlassian products (Jira, Confluence, etc). Looks like this question might be better suited for your company's internal IT department.
Generally, API access to Slack now involves creating a Slack app and using scoped tokens. However, Splunk does have an app in the Slack app directory that you can install to greatly simplify this process. Whichever team in your company that maintains your Slack workspace (usually an IT team) can check it out:
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