Those panel antennae must have been very weak for a omni-direcitonal to outperform it. 
The omni-directional antenna is probably only working due to the thick walls preventing a feedback loop. Generally repeaters require a directional outdoor antenna facing away from the house. When the outdoor antenna transmits back to the mast, this signal must not reach the indoor antenna, which can happen with an outdoor omni-directional antenna that radiates the signal evenly around the antenna including towards the house. This can create a feedback loop, like a microphone placed near its PA speaker, which will cause the repeater to either reduce its gain or shutdown (legal requirement to prevent swamping the cellular network with the resulting RF noise).
I suggest getting a directional antenna (e.g. Poynting's directional model 4G-XPOL-A0002) and install that outside, aimed towards the mast. Then install your Poynting omni-directional antenna somewhere central inside.
Repeaters have a legal limit on how much power they can transmit indoors, which is similar to a Wi-Fi router. If you use your omni-directional antenna inside, it will distribute the signal evenly around, which basically means the surrounding rooms 1 wall apart should have a good signal.
The omni-directional antenna is probably only working due to the thick walls preventing a feedback loop. Generally repeaters require a directional outdoor antenna facing away from the house. When the outdoor antenna transmits back to the mast, this signal must not reach the indoor antenna, which can happen with an outdoor omni-directional antenna that radiates the signal evenly around the antenna including towards the house. This can create a feedback loop, like a microphone placed near its PA speaker, which will cause the repeater to either reduce its gain or shutdown (legal requirement to prevent swamping the cellular network with the resulting RF noise).
I suggest getting a directional antenna (e.g. Poynting's directional model 4G-XPOL-A0002) and install that outside, aimed towards the mast. Then install your Poynting omni-directional antenna somewhere central inside.
Repeaters have a legal limit on how much power they can transmit indoors, which is similar to a Wi-Fi router. If you use your omni-directional antenna inside, it will distribute the signal evenly around, which basically means the surrounding rooms 1 wall apart should have a good signal.