murdocklawless what happens when you visit the forum? Do you see the old image, do you see the forum title or do you see nothing where the logo/title is supposed to be?
You can use the browser development tools to inspect the src attribute of the image and/or the network tab to check whether the image load encounters a 404 error.
If the src is correct and there's no 404, maybe the image is just 0 pixels by 0 pixels. Depending on the viewport configured in the SVG file you might need to update it, or change the CSS to force a different width/height.
Are you able to share the svg file or a link to your forum?