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Ok. You first need to determine if you need to rack in to achieve focus or out. Out is easy, first rack out all the way with the 10mm eyepiece in place and then slide the eyepiece out by loosening the eyepiece lock screw or even the 2" lock screw and move the 2"/1.25" adaptor out a bit. If you can get focus then all you need is an extension tube, 35mm no more.
If you need to rack in to achieve focus but cannot rack in any further then you may be able to 'push' the focal plane out further by loosening all collimation screws on the primary mirror and then re-collimation by adjusting two of the three screws as needed. This may give you enough to reach focus. Another more drastic method would be to shift the entire primary mirror and cell up the tube a small amount.
It would be very unusual if your 10mm eyepiece did not focus and perhaps collimation (or lack thereof) and bad seeing had contributed to what appears to be an out of focus image on the night you were viewing.
Dont worry about the fine focus as it is not essential. In fact sometimes the human eye can adjust to a slightly out of focus image before you get your fine focus spot on. Some people like the fine focus though and it is highly recommended for imaging. If you cannot get course focus on your object then fine focus will not help at all.
Note too if your focal plane is only a little out past the fully racked out position then you can tighten all collimation screws on the primary mirror to bring it it and loosen two only as needed to re-collimate.
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