It's been a long time since I used the ticket system, but if there isn't some kind of "escalate" button, you can always request in the ticket that the matter be brought to the attention of a supervisor. Please don't use this out of impatience, but only if you feel the current level of support is not doing a good job or is dragging their feet.
If your site is malware-infected, have they told you what to look for? Presumably you're using some sort of canned application, such as Wordpress (it's very rare to infect written-from-scratch sites). You should have a backup from before the problems started, that you could restore, or at least, compare to see what was infected or added. If you do restore an older backup, you'll need to understand how you got infected, so you can immediately plug that hole before it happens again. LP keeps backups for only a few days, so you'll have to have made your own backup for this to work. Be sure to keep your application(s) up to date, as they're constantly being patched to plug security holes. Any database may have to be inspected and cleaned, too.