Points not plotting with reference to x-tick labels

[Mark17]

Here's the graphing portion of my program:

fig, axs = plt.subplots(1,1) 
fig.set_size_inches(14, 6)

axs.plot(trade_list,P_price_orig_all, marker='o', color='orange')
ax1twin = axs.twinx()
ax1twin.plot(btstats['Date'],btstats['SPX'],marker='',color='blue',linestyle='solid') #May still have to include y-axis label.
axs.set_xticks(list(np.linspace(1,len(btstats.index),num=len(xtick_labels_converted))),xtick_labels_converted, rotation=45)

plt.show()

I spend all those hours figuring out L7 to get evenly spaced (in time) dates to print out evenly spaced across the x-axis. However, trade_list (a list of dates) is not evenly spaced in time. These points print out evenly spaced--not in reference to the date values now shown on the x-axis:

https://ibb.co/z7021yD

What have I done?

Incidentally, if I comment out L5, the blue line goes away and the orange line/markers get compressed on the left side of the graph. This make some sense because len(trade_list) is 255 and len(btstats['SPX']) is 3449. I just want the 255 points to print accordingly where their x-values match up with those on the x-axis.